Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 4,346		$ 2,168		$ 5,299		$ 4,566
Currency translation adjustment-net of tax	(8)	[1]			(4)	[1]
Reclassification of derivative gains to earnings-net of tax	143	[2]	(444)	[2]	(263)	[2]	(1,067)	[2]
Change in fair value of derivatives-net of tax	(1,905)	[3]	(370)	[3]	(1,025)	[3]	819	[3]
Other comprehensive income (loss)-net of tax, Total	(1,770)		(814)		(1,292)		(248)
Comprehensive income	2,576		1,354		4,007		4,318
Comprehensive (income) loss attributable to noncontrolling interests	91		(462)		206		(468)
Comprehensive income attributable to Great Lakes Dredge & Dock Corporation	$ 2,667		$ 892		$ 4,213		$ 3,850

[1] Net of income tax (expense) benefit of $(5) and $0 for the three months ended June 30, 2012 and 2011, respectively, and $(3) and $0 for the six months ended June 30, 2012 and 2011, respectively.

[2] Net of income tax (expense) benefit of $94 and $(295) for the three months ended June 30, 2012 and 2011, respectively, and $(175) and $(709) for the six months ended June 30, 2012 and 2011, respectively.

[3] Net of income tax (expense) benefit of $(1,265) and $(246) for the three months ended June 30, 2012 and 2011, respectively, and $(681) and $544 for the six months ended June 30, 2012 and 2011, respectively.