Subsidiary Guarantors (Condensed Consolidated Statement Operations And Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Condensed Financial Statements, Captions [Line Items]
Contract revenues	$ 192,192	$ 238,877	$ 355,311	$ 413,434
Costs of contract revenues	(167,936)	(206,590)	(311,065)	(370,465)
Gross profit	24,256	32,287	44,246	42,969
General and administrative expenses	19,751	15,543	39,840	33,491
Impairment of goodwill		2,750		2,750
(Gain) loss on sale of assets—net	687	5	677	(3)
Operating income	3,818	13,989	3,729	6,731
Interest expense—net	(5,903)	(5,567)	(11,624)	(11,197)
Equity in earnings (loss) of joint ventures	128	(2,616)	13	(3,714)
Other income (expense)	(518)	(618)	(1,281)	(1,059)
Income (loss) before income taxes	(2,475)	5,188	(9,163)	(9,239)
Income tax (provision) benefit	756	(2,464)	3,409	3,573
Net income (loss)	(1,719)	2,724	(5,754)	(5,666)
Comprehensive income (loss)	(1,571)	2,777	(5,197)	(6,421)
Consolidation Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues	(517)	(592)	(977)	(1,581)
Costs of contract revenues	517	592	977	1,581
Equity in earnings (loss) of subsidiaries	(3,094)	(10,696)	(1,863)	(1,523)
Income (loss) before income taxes	(3,094)	(10,696)	(1,863)	(1,523)
Net income (loss)	(3,094)	(10,696)	(1,863)	(1,523)
Comprehensive income (loss)	(3,242)	(10,749)	(2,420)	(768)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues	192,709	235,151	356,288	407,505
Costs of contract revenues	(167,005)	(203,184)	(309,188)	(364,388)
Gross profit	25,704	31,967	47,100	43,117
General and administrative expenses	19,806	15,543	39,891	33,491
Impairment of goodwill		2,750		2,750
(Gain) loss on sale of assets—net	687	5	677	(3)
Operating income	5,211	13,669	6,532	6,879
Interest expense—net	(184)	40	(365)	(259)
Equity in earnings (loss) of subsidiaries	(96)		(178)	4
Equity in earnings (loss) of joint ventures	128	(2,616)	13	(3,714)
Other income (expense)	(518)	(618)	(1,273)	(1,052)
Income (loss) before income taxes	4,541	10,475	4,729	1,858
Income tax (provision) benefit	1
Net income (loss)	4,542	10,475	4,729	1,858
Comprehensive income (loss)	4,542	10,475	4,729	1,858
Non Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues		4,318		7,510
Costs of contract revenues	(1,448)	(3,998)	(2,854)	(7,658)
Gross profit	(1,448)	320	(2,854)	(148)
General and administrative expenses			4
Operating income	(1,448)	320	(2,858)	(148)
Other income (expense)			(8)	(7)
Income (loss) before income taxes	(1,448)	320	(2,866)	(155)
Income tax (provision) benefit		(99)		(180)
Net income (loss)	(1,448)	221	(2,866)	(335)
Comprehensive income (loss)	(1,300)	274	(2,309)	(1,090)
GLDD Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
General and administrative expenses	(55)		(55)
Operating income	55		55
Interest expense—net	(5,719)	(5,607)	(11,259)	(10,938)
Equity in earnings (loss) of subsidiaries	3,190	10,696	2,041	1,519
Income (loss) before income taxes	(2,474)	5,089	(9,163)	(9,419)
Income tax (provision) benefit	755	(2,365)	3,409	3,753
Net income (loss)	(1,719)	2,724	(5,754)	(5,666)
Comprehensive income (loss)	$ (1,571)	$ 2,777	$ (5,197)	$ (6,421)