Subsidiary Guarantors (Condensed Consolidated Statement Operations And Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Contract revenues	$ 163,119	$ 174,557
Costs of contract revenues	(143,129)	(163,875)
Gross profit	19,990	10,682
General and administrative expenses	20,089	17,948
(Gain) loss on sale of assets—net	(10)	(8)
Operating loss	(89)	(7,258)
Interest expense—net	(5,721)	(5,630)
Equity in loss of joint ventures	(115)	(1,098)
Other income (expense)	(763)	(441)
Loss before income taxes	(6,688)	(14,427)
Income tax benefit	2,653	6,037
Net loss	(4,035)	(8,390)
Comprehensive income (loss)	(3,626)	(9,198)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues	163,579	172,354
Costs of contract revenues	(142,183)	(161,204)
Gross profit	21,396	11,150
General and administrative expenses	20,085	17,948
(Gain) loss on sale of assets—net	(10)	(8)
Operating loss	1,321	(6,790)
Interest expense—net	(181)	(299)
Equity in earnings (loss) of subsidiaries	(82)	4
Equity in loss of joint ventures	(115)	(1,098)
Other income (expense)	(755)	(434)
Loss before income taxes	188	(8,617)
Income tax benefit	(1)
Net loss	187	(8,617)
Comprehensive income (loss)	187	(8,617)
Non Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues		3,192
Costs of contract revenues	(1,406)	(3,660)
Gross profit	(1,406)	(468)
General and administrative expenses	4
Operating loss	(1,410)	(468)
Other income (expense)	(8)	(7)
Loss before income taxes	(1,418)	(475)
Income tax benefit		(81)
Net loss	(1,418)	(556)
Comprehensive income (loss)	(1,009)	(1,364)
Consolidation Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Contract revenues	(460)	(989)
Costs of contract revenues	460	989
Equity in earnings (loss) of subsidiaries	1,231	9,173
Loss before income taxes	1,231	9,173
Net loss	1,231	9,173
Comprehensive income (loss)	822	9,981
GLDD Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
Interest expense—net	(5,540)	(5,331)
Equity in earnings (loss) of subsidiaries	(1,149)	(9,177)
Loss before income taxes	(6,689)	(14,508)
Income tax benefit	2,654	6,118
Net loss	(4,035)	(8,390)
Comprehensive income (loss)	$ (3,626)	$ (9,198)