Selected Balance Sheet Accounts (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Inventory:
Inventory for remotely operated vehicles	$ 174,612	$ 135,297
Other inventory, primarily raw materials	156,668	119,798
Total	331,280	255,095
Other Current Assets:
Deferred income taxes	22,604	20,718
Prepaid expenses	61,627	52,355
Total	84,231	73,073
Other Non-Current Assets:
Intangible assets	78,252	70,611
Cash surrender value of life insurance policies	42,841	38,318
Long-term portion of accounts receivable, net	0	21,658
Other	13,091	9,449
Total	134,184	140,036
Accrued Liabilities:
Payroll and related costs	218,609	191,430
Accrued job costs	75,037	51,296
Deferred revenue, including billings in excess of revenue recognized	73,465	52,132
Other	41,192	40,303
Total	408,303	335,161
Other Long-Term Liabilities:
Deferred income taxes	178,100	157,532
Supplemental Executive Retirement Plan	35,772	34,768
Accrued post-employment benefit obligations	12,942	13,935
Other	14,659	14,972
Total	$ 241,473	$ 221,207