Document and Entity Information Document And Entity Information [Abstract] Statement [Table] Statement [Line Items] Document Type Amendment Flag Document Period End Date Document Fiscal Year Focus Document Fiscal Period Focus Trading Symbol Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Public Float Entity Current Reporting Status Entity Voluntary Filers Consolidated Balance Sheets [Abstract] Assets Abstract ASSETS Cash and cash equivalents Cash and cash equivalents at end of year Cash and cash equivalents at beginning of year Cash and cash equivalents Accounts receivable2 Accounts receivable-net Accounts receivable - net Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year Contract revenues in excess of billings Inventory Net Inventories Inventories Prepaid expenses Prepaid expenses Other current assets Assets, Current Total current assets PROPERTY AND EQUIPMENT - Net Property, Plant and Equipment, Net, Ending Balance Property, Plant and Equipment, Net, Beginning Balance PROPERTY AND EQUIPMENT-Net PROPERTY AND EQUIPMENT - Net GOODWILL Goodwill, Ending Balance Goodwill, Beginning Balance Goodwill, Total OTHER INTANGIBLE ASSETS - Net OTHER INTANGIBLE ASSETS-Net OTHER INTANGIBLE ASSETS - Net INVENTORIES - Noncurrent INVENTORIES-Noncurrent INVENTORIES - Noncurrent INVESTMENTS IN JOINT VENTURES INVESTMENTS IN JOINT VENTURES Othe rAssets Noncurrent OTHER Other Assets, Noncurrent, Total Assets TOTAL Liabilities and Equity [Abstract] LIABILITIES AND EQUITY Accounts payable Accounts Payable, Current, Total Accrued Liabilities Current Accrued expenses Accrued Liabilities, Current, Total Billings in excess of contract revenues Billings in Excess of Cost, Total Notes Payable, Current Current portion of note payable Notes Payable, Current, Total Capital Lease Obligations, Current Current portion of equipment debt Liabilities, Current Total current liabilities Notes Payable, Noncurrent LONG TERM NOTE PAYABLE Notes Payable, Noncurrent, Total Senior Notes 7 3/8% SENIOR NOTES Senior Notes, Total 7 3/4 % SENIOR SUBORDINATED NOTES 7 3/4% SENIOR SUBORDINATED NOTES DEFERRED INCOME TAXES OTHER Other Liabilities, Noncurrent, Total Liabilities Total liabilities COMMITMENTS ANDCONTINGENCIES COMMITMENTS AND CONTINGENCIES (Note 12) EQUITY: Common stock-$.0001 par value; 90,000,000 authorized, 58,671,956 and 58,542,038 shares issued and outstanding at June 30, 2010 and December 31, 2009, respectively. Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued, Beginning Balance Common stock-$.0001 par value; 90,000,000 authorized, 58,999,404 and 58,770,369 shares issued and outstanding at December 31, 2011 and December 31, 2010, respectively. Common Stock, Value, Issued, Total Additional paid-in capital Additional Paid in Capital, Ending Balance Additional Paid in Capital, Beginning Balance Additional paid-in capital Accumulated deficit Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit), Beginning Balance Retained earnings Accumulated deficit Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated other comprehensive income Accumulated other comprehensive income (loss) Stockholders' Equity Attributable to Parent BALANCE - Value BALANCE - Value Total Great Lakes Dredge & Dock Corporation equity NONCONTROLLING INTERESTS NONCONTROLLING INTERESTS Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance Stockholders' Equity Attributable to Noncontrolling Interest, Total Acquisition of Yankee Environmental Services Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest BALANCE - Value BALANCE - Value Total equity Liabilities and Equity TOTAL Common Stock, Par Value Common stock, par value Common Stock, Shares authorized Common stock, shares authorized Common Stock, Shares issued Common stock, shares issued Common Stock, Shares, Issued, Total Common Stock, Shares outstanding Common Stock, Shares, Outstanding, Ending Balance Common Stock, Shares, Outstanding, Beginning Balance Common stock, shares outstanding Consolidated Statements Of Operations [Abstract] Contract revenues Contract revenues CONTRACT REVENUES Costs of contract revenues COSTS OF CONTRACT REVENUES Gross Profit GROSS PROFIT Operating Expenses [Abstract] OPERATING EXPENSES: General and administrative expenses General and administrative expenses GENERAL AND ADMINISTRATIVE EXPENSES General and administrative expenses Gain (Loss) on Sale of Other Assets GAIN ON SALE OF ASSETS-Net Operating Income (Loss) Total operating income Other Nonoperating Income (Expense) [Abstract] OTHER EXPENSE: Interest expense - net Interest expense-net Interest Income (Expense), Net, Total Equity in loss of joint ventures Equity in loss of joint ventures Equity in loss of joint ventures Income (Loss) from Equity Method Investments, Total Foreign Currency Transaction Loss, before Tax Loss on foreign currency transactions-net Loss on foreign currency transactions - net Gains (Losses) on Extinguishment of Debt Loss on extinguishment of 7 3/4% senior subordinated notes Loss on extinguishment of debt Gains (Losses) on Extinguishment of Debt, Total Loss on extinguishment of 7.75% senior subordinated notes Other Nonoperating Income (Expense) Total other expense Total other expense Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest INCOME BEFORE INCOME TAXES Income tax provision INCOME TAX EXPENSE Income tax provision Net income Net income NET INCOME Net income (loss) Net loss attributable to noncontrolling interests Net (income) loss attributable to noncontrolling interests Net loss attributable to noncontrolling interests Net Income (Loss) Attributable to Parent NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS OF GREAT LAKES DREDGE & DOCK CORPORATION Basic earnings per share attributable to Great Lakes Dredge & Dock Corporation Basic earnings per share attributable to Great Lakes Dredge & Dock Corporation Basic weighted average shares Weighted Average Number of Shares Outstanding, Basic, Total Basic weighted-average shares Diluted earnings per share attributable to Great Lakes Dredge & Dock Corporation Diluted earnings per share attributable to Great Lakes Dredge & Dock Corporation Diluted weighted average shares Weighted Average Number of Shares Outstanding, Diluted, Total Diluted weighted-average shares Consolidated Statements Of Equity [Abstract] Statement, Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Parent [Member] Parent [Member] Common Stock [Member] Common Stock [Member] Additional Paid In Capital [Member] Additional Paid-In Capital [Member] Retained Earnings [Member] Retained Earnings (Accumulated Deficit) [Member] Accumulated Other Comprehensive Income [Member] Accumulated Other Comprehensive Income (Loss)[Member] Noncontrolling Interest [Member] Noncontrolling Interests [Member] Shares, Issued BALANCE - Shares BALANCE - Shares Noncontrolling Interest, Increase from Business Combination Acquisition of Yankee Environmental Services Share-based compensation, Value Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures, Total Share-based compensation, Shares Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures, Total Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total Vesting of restricted stock units, including impact of shares withheld for taxes, value Vesting of RSU's Vesting of restricted stock units, including impact of shares withheld for taxes Vesting of restricted stock units, including impact of shares withheld for taxes, shares Vesting of RSU's Exercise of stock options, Value Exercise of stock options, Shares Excess Tax Benefit from Share-based Compensation, Operating Activities Excess income tax benefit from share-based compensation Excess income tax benefit from share-based compensation Excess income tax benefit from share based compensation Acquisition of Noncontrolling Interest Acquisition Of Noncontrolling Interest, Acquisition of noncontrolling interest in NASDI, LLC Acquisition of noncontrolling interest in NASDI, LLC Dividends, Cash Dividends declared and paid Dividends, Cash, Total Dividends, Share-based Compensation Dividend equivalents paid on restricted stock units Dividends, Share-based Compensation, Total Dividend equivalents paid on restricted stock units Comprehensive income (loss): Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Currency translation adjustment (net of tax of $177) Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total Reclassification of derivative gain (loss) to earnings Reclassification of derivative gains (losses) to earnings, net of tax Reclassification of derivative gains to earnings, net of tax Change in fair value of derivatives Change in fair value of derivatives, net of tax Total comprehensive income (loss) Total comprehensive income (loss): Dividends per share declared and paid. Dividends per Share Declared and Paid Dividends declared and paid, per share Reclassification of derivative gains (losses) to earnings, tax Change in fair value of derivatives, tax Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Currency translation adjustment, tax Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Total Consolidated Statements Of Cash Flows [Abstract] OPERATING ACTIVITIES: Adjustments to reconcile net income to net cash flows provided by operating activities: Depreciation and amortization Depreciation and amortization Equity Method Investment, Dividends or Distributions Distribution from equity joint ventures Deferred Income Tax Expense Benefit Deferred income taxes Deferred Income Tax Expense (Benefit), Total Gain on dispositions of property and equipment GAIN ON SALE OF ASSETS- Net Gain on dispositions of property and equipment Gain on sale of assets, net Gain on dispositions of property and equipment Gain on adjustment of contingent earnout. Gain on Adjustment of Contingent Earnout Gain on adjustment of contingent earnout Gain on adjustment of contingent earnout Amortization of deferred financing fees Foreign Currency Transaction Gain (Loss), Unrealized Unrealized foreign currency loss Unrealized foreign currency loss Share-based compensation expense Share-based compensation expense Changes in assets and liabilities: Accounts receivable 1 Accounts receivable Contract revenues in excess of billings. Contract Revenues in Excess of Billings Contract revenues in excess of billings Inventories Inventories Inventories Prepaid expenses and other current assets Prepaid expenses and other current assets Prepaid expenses and other current assets Accounts payable and accrued expenses Accounts payable and accrued expenses Increase (decrease) in Billings in excess of contract revenues Increase Decrease In Billings In Excess Of Contract Revenues Billings in excess of contract revenues Other noncurrent assets and liabilities Other noncurrent assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net, Total Net Cash Provided by (Used in) Operating Activities Net cash flows provided by operating activities INVESTING ACTIVITIES: Purchases of property and equipment Purchases of property and equipment Purchases of property and equipment Dispositions of property and equipment Proceeds from dispositions of property and equipment Dispositions of property and equipment Payments to Acquire Businesses, Net of Cash Acquired Acquisition of Matteson assets Purchase of Matteson Payments to Acquire Businesses, Net of Cash Acquired, Total Payments to Acquire Interest in Subsidiaries and Affiliates Acquisition of controlling interest in Yankee Environmental Services Acquisition of controlling interest in Yankee Environmental Services Payments to Acquire Interest in Subsidiaries and Affiliates, Total Net Cash Provided by (Used in) Investing Activities Net cash flows used in investing activities FINANCING ACTIVITIES: Proceeds from Issuance of Senior Long-term Debt Proceeds from issuance of 7.375% senior notes Proceeds from issuance of 7 3/8% senior notes Repayments of Subordinated Debt Redemption of 7 3/4% senior subordinated notes Redemption of 7.75% senior subordinated notes Repayments of Subordinated Debt, Total Senior Subordinated Notes Redemption Premium Senior Subordinated Notes Redemption Premium Senior subordinated notes redemption premium Senior subordinated notes redemption premium Payment of Financing and Stock Issuance Costs Deferred financing fees Deferred financing fees Payment of Financing and Stock Issuance Costs, Total Repayments of Long-term Debt Repayment of long term note payable Repayment of long term note payable Repayments of Long-term Debt, Total Dividends paid Dividends paid Dividends paid Taxes paid on vested share awards. Taxes Paid on Vested Share Awards Taxes paid on settlement of vested share awards Repayment of capital lease debt Repayments of equipment debt Repayments of equipment debt Exercise of stock options Excess Tax Benefit from Share-based Compensation, Financing Activities Excess income tax benefit from share-based compensation Borrowings under revolving loans Repayments of revolving loans Repayments of revolving loans Net Cash Provided by (Used in) Financing Activities Net cash flows provided by (used in) financing activities Effect of Exchange Rate on Cash and Cash Equivalents Effect of foreign currency exchange rates on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents, Total Cash and Cash Equivalents, Period Increase (Decrease) Net increase (decrease) in cash and cash equivalents Supplemental Cash Flow Information Cash paid for interest Interest Paid, Net, Total Cash paid for income taxes Non-cash Investing Activity Property and equipment purchased but not yet paid Future cash outflows to pay for purchases of property and equipment that are financed by notes. Property and equipment purchased on equipment notes Property and equipment purchased on capital leases and equipment notes Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed) Acquisition of noncontrolling interest in NASDI, LLC Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed), Total Acquisition of noncontrolling interest in NASDI, LLC Noncash or Part Noncash Acquisition, Value of Liabilities Assumed Noncash or Part Noncash Acquisition, Value of Liabilities Assumed Noncash or Part Noncash Acquisition, Value of Liabilities Assumed, Total Purchase price of Matteson assets comprised of promissory notes and other liabilities Nature Of Business And Summary Of Significant Accounting Policies [Abstract] Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Nature Of Business And Summary Of Significant Accounting Policies Restricted and escrowed cash. Restricted And Escrowed Cash [Abstract] Restricted and escrowed cash. Restricted And Escrowed Cash [Text Block] Restricted And Escrowed Cash Accounts Receivable And Contracts In Progress [Abstract] Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Accounts Receivable And Contracts In Progress Property And Equipment [Abstract] Property, Plant and Equipment Disclosure [Text Block] Property And Equipment Goodwill And Other Intangible Assets [Abstract] Goodwill and Intangible Assets Disclosure [Text Block] Goodwill And Other Intangible Assets Accrued Expenses [Abstract] Accounts Payable and Accrued Liabilities Disclosure [Text Block] Accrued Expenses Long-Term Debt [Abstract] Long-term Debt [Text Block] Long-Term Debt Fair Value Measurements [Abstract] Fair value measurements [Text Block] Fair Value Measurements Income Taxes [Abstract] Income Tax Disclosure [Text Block] Income Taxes Share-Based Compensation [Abstract] Share-based compensation Share-Based Compensation Retirement Plans [Abstract] Pension and Other Postretirement Benefits Disclosure [Text Block] Retirement Plans Commitments And Contingencies [Abstract] Commitments And Contingencies Disclosure Text Block Commitments And Contingencies Related-Party Transactions [Abstract] Related Party Transactions Disclosure [Text Block] Related-Party Transactions Business Combinations And Reorganizations [Abstract] Business Acquisition, Integration, Restructuring and Other Related Costs [Text Block] Business Combinations And Reorganizations Segment Information [Abstract] Segment Reporting Disclosure [Text Block] Segment Information Subsidiary guarantors [Abstract]. Subsidiary Guarantors [Abstract] Subsidiary guarantors [Text Block]. Subsidiary Guarantors [Text Block] Subsidiary Guarantors