Selected Balance Sheet Accounts (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Inventory:
Inventory for remotely operated vehicles	$ 135,297	$ 119,106
Other inventory, primarily raw materials	119,798	117,411
Total	255,095	236,517
Other Current Assets:
Deferred income taxes	20,718	28,494
Prepaid expenses	52,355	49,258
Total	73,073	77,752
Other Non-Current Assets:
Intangible assets	70,611	22,208
Cash surrender value of life insurance policies	38,318	36,339
Long-term portion of accounts receivable, net	21,658	0
Other	9,449	7,030
Total	140,036	65,577
Accrued Liabilities:
Payroll and related costs	191,430	168,476
Accrued job costs	51,296	50,323
Deferred revenue, including billings in excess of revenue recognized	52,132	68,131
Other	40,303	27,480
Total	335,161	314,410
Other Long-Term Liabilities:
Deferred income taxes	157,532	139,822
Supplemental Executive Retirement Plan	34,768	32,341
Accrued post-employment benefit obligations	13,935	14,245
Other	14,972	14,027
Total	$ 221,207	$ 200,435