Discontinued Operations (Details 2) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		1 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Oil and Gas	Sep. 30, 2011 Oil and Gas	Sep. 30, 2012 Oil and Gas	Sep. 30, 2011 Oil and Gas	Apr. 30, 2012 Oil and Gas Columbia	Sep. 30, 2012 Oil and Gas United States	May 31, 2012 Oil and Gas United States	Sep. 30, 2012 Other Rig Services	Sep. 30, 2011 Other Rig Services	Sep. 30, 2012 Other Rig Services	Sep. 30, 2011 Other Rig Services	Sep. 30, 2012 Other Rig Services Aircraft logistics assets	Sep. 30, 2011 Other Rig Services Remora
Condensed Statements of Income
Operating revenues and Earnings (losses) from unconsolidated affiliates					$ 12,859,000	$ 10,630,000	$ 19,079,000	$ 116,046,000				$ 8,334,000	$ 9,341,000	$ 18,750,000	$ 21,180,000
Income (loss) from discontinued operations
Income (loss) from discontinued operations					5,826,000	(20,167,000)	(2,095,000)	42,746,000				2,199,000	2,336,000	(3,320,000)	(1,197,000)
Gain (loss) on sale or disposal of wholly owned assets					3,662,000		39,772,000	39,944,000	48,500,000	3,700,000		(2,554,000)		(7,796,000)
Less: income tax expense (benefit)					(1,604,000)	(6,189,000)	2,623,000	(14,752,000)				(89,000)	584,000	(2,783,000)	(300,000)
Income (loss) from discontinued operations, net of tax	10,826,000	(12,226,000)	26,721,000	96,545,000								(266,000)	1,752,000	(8,333,000)	(897,000)
Equity in earnings	(99,527,000)	33,723,000	(302,513,000)	59,305,000													85,000,000
Sale of business
Sale price									72,600,000	7,300,000	5,700,000
Gain on sale of oil and gas operations					3,662,000		39,772,000	39,944,000	48,500,000	3,700,000		(2,554,000)		(7,796,000)
Impairment of logistics assets																$ 7,800,000