Segment Information (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Summary of financial information for the Company's segments
Revenues	$ 565,342	$ 435,353	$ 1,490,129	$ 1,224,720
Cost of services (exclusive of items shown separately below)	301,065	232,308	806,280	661,276
Depreciation, depletion, amortization and accretion	64,875	56,805	187,552	162,152
General and administrative expenses	95,391	84,912	278,151	248,165
Gain on sale of businesses			8,558
Income (loss) from operations	104,011	61,328	226,704	153,127
Interest income (expense), net	(19,115)	(12,456)	(47,940)	(39,174)
Earnings from equity-method investments, net	8,198	3,030	13,724	9,185
Income (loss) before income taxes	93,094	51,902	192,488	123,138
Identifiable Assets
Identifiable Assets, Total	3,483,742		3,483,742		2,907,533
Subsea and Well Enhancement [Member]
Summary of financial information for the Company's segments
Revenues	377,559	289,048	975,641	806,166
Cost of services (exclusive of items shown separately below)	228,241	170,817	593,216	481,561
Depreciation, depletion, amortization and accretion	28,976	25,162	82,773	69,254
General and administrative expenses	64,812	53,043	182,279	158,746
Income (loss) from operations	55,530	40,026	117,373	96,605
Interest income (expense), net	1,248	1,343	3,483	3,500
Income (loss) before income taxes	56,778	41,369	120,856	100,105
Identifiable Assets
Identifiable Assets, Total	2,095,664		2,095,664		1,769,813
Drilling Products and Services [Member]
Summary of financial information for the Company's segments
Revenues	163,456	118,727	440,893	354,341
Cost of services (exclusive of items shown separately below)	58,538	46,068	161,862	129,922
Depreciation, depletion, amortization and accretion	33,213	28,846	96,220	85,135
General and administrative expenses	28,676	28,394	88,416	79,584
Income (loss) from operations	43,029	15,419	94,395	59,700
Income (loss) before income taxes	43,029	15,419	94,395	59,700
Identifiable Assets
Identifiable Assets, Total	1,041,475		1,041,475		802,785
Marine [Member]
Summary of financial information for the Company's segments
Revenues	24,327	27,578	73,595	64,213
Cost of services (exclusive of items shown separately below)	14,286	15,423	51,202	49,793
Depreciation, depletion, amortization and accretion	2,686	2,797	8,559	7,763
General and administrative expenses	1,903	3,475	7,456	9,835
Gain on sale of businesses			8,558
Income (loss) from operations	5,452	5,883	14,936	(3,178)
Income (loss) before income taxes	5,452	5,883	14,936	(3,178)
Identifiable Assets
Identifiable Assets, Total	249,532		249,532		255,883
Unallocated [Member]
Summary of financial information for the Company's segments
Interest income (expense), net	(20,363)	(13,799)	(51,423)	(42,674)
Earnings from equity-method investments, net	8,198	3,030	13,724	9,185
Income (loss) before income taxes	(12,165)	(10,769)	(37,699)	(33,489)
Identifiable Assets
Identifiable Assets, Total	$ 97,071		$ 97,071		$ 79,052