Subsidiary Guarantors (Condensed Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
ASSETS
Cash and cash equivalents	$ 11,167	$ 14,184	$ 42,389	$ 75,338
Accounts receivable—net	88,091	130,777
Contract revenues in excess of billings	95,012	81,195
Inventories	37,137	35,963
Prepaid expenses	12,407	7,924
Other current assets	63,412	59,690
Total current assets	307,226	329,733
PROPERTY AND EQUIPMENT—Net	413,008	430,210	399,445
GOODWILL	83,576	83,576	86,326
OTHER INTANGIBLE ASSETS — Net	1,499	2,428
INVENTORIES—Noncurrent	52,602	41,646
INVESTMENTS IN JOINT VENTURES	4,734	3,761	7,889
ASSETS HELD FOR SALE— Noncurrent	9,299
OTHER	21,644	6,770
TOTAL	893,588	898,124	889,732
LIABILITIES AND EQUITY
Accounts payable	103,185	118,846
Accrued expenses	69,043	72,277
Billings in excess of contract revenues	5,141	7,061
Current portion of long term debt	2,465	7,506
Total current liabilities	179,834	205,690
7 3/8% SENIOR NOTES	272,998	271,998
REVOLVING CREDIT FACILITY	104,111	20,000
NOTE PAYABLE	13,293	53,792
DEFERRED INCOME TAXES	68,449	74,006
OTHER	7,013	20,465
Total liabilities	645,698	645,951
TOTAL EQUITY	247,890	252,173	255,963	242,101
TOTAL	893,588	898,124
Guarantor Subsidiaries [Member]
ASSETS
Cash and cash equivalents	11,037	12,035	41,724	71,939
Accounts receivable—net	86,690	129,978
Contract revenues in excess of billings	94,731	79,477
Inventories	37,137	35,963
Prepaid expenses	12,407	7,924
Other current assets	63,089	58,995
Total current assets	305,091	324,372
PROPERTY AND EQUIPMENT—Net	413,002	430,192
GOODWILL	83,576	83,576
OTHER INTANGIBLE ASSETS — Net	1,499	2,428
INVENTORIES—Noncurrent	52,602	41,646
INVESTMENTS IN JOINT VENTURES	4,734	3,761
ASSETS HELD FOR SALE— Noncurrent	9,299
RECEIVABLES FROM AFFILIATES	11,524	18,326
INVESTMENTS IN SUBSIDIARIES	3,695	3,706
OTHER	14,692	6,702
TOTAL	899,714	914,709
LIABILITIES AND EQUITY
Accounts payable	102,654	118,619
Accrued expenses	58,192	62,861
Billings in excess of contract revenues	4,963	6,964
Current portion of long term debt	1,320	1,424
Total current liabilities	167,129	189,868
NOTE PAYABLE		323
DEFERRED INCOME TAXES	(1,833)	(783)
PAYABLES TO AFFILIATES	88,573	85,859
OTHER	6,862	20,326
Total liabilities	260,731	295,593
TOTAL EQUITY	638,983	619,116
TOTAL	899,714	914,709
Non Guarantor Subsidiaries [Member]
ASSETS
Cash and cash equivalents	128	2,147	663	$ 3,399
Accounts receivable—net	1,401	799
Contract revenues in excess of billings	281	1,718
Other current assets	323	218
Total current assets	2,133	4,882
PROPERTY AND EQUIPMENT—Net	6	18
RECEIVABLES FROM AFFILIATES	6,883	6,009
OTHER	1	3
TOTAL	9,023	10,912
LIABILITIES AND EQUITY
Accounts payable	514	227
Accrued expenses	970	509
Billings in excess of contract revenues	178	97
Total current liabilities	1,662	833
PAYABLES TO AFFILIATES	6,433	3,505
Total liabilities	8,095	4,338
TOTAL EQUITY	928	6,574
TOTAL	9,023	10,912
GLDD Corporation [Member]
ASSETS
Cash and cash equivalents	2	2	$ 2
Other current assets		477
Total current assets	2	479
RECEIVABLES FROM AFFILIATES	82,340	70,738
INVESTMENTS IN SUBSIDIARIES	636,216	621,984
OTHER	6,951	65
TOTAL	725,509	693,266
LIABILITIES AND EQUITY
Accounts payable	17
Accrued expenses	9,881	8,907
Current portion of long term debt	1,145	6,082
Total current liabilities	11,043	14,989
7 3/8% SENIOR NOTES	272,998	271,998
REVOLVING CREDIT FACILITY	104,111	20,000
NOTE PAYABLE	13,293	53,469
DEFERRED INCOME TAXES	70,282	74,789
PAYABLES TO AFFILIATES	5,741	5,709
OTHER	151	139
Total liabilities	477,619	441,093
TOTAL EQUITY	247,890	252,173
TOTAL	725,509	693,266
Consolidation Eliminations [Member]
ASSETS
RECEIVABLES FROM AFFILIATES	(100,747)	(95,073)
INVESTMENTS IN SUBSIDIARIES	(639,911)	(625,690)
TOTAL	(740,658)	(720,763)
LIABILITIES AND EQUITY
PAYABLES TO AFFILIATES	(100,747)	(95,073)
Total liabilities	(100,747)	(95,073)
TOTAL EQUITY	(639,911)	(625,690)
TOTAL	$ (740,658)	$ (720,763)