Discontinued Operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Operating Revenues	$ 338,936	$ 336,784	$ 977,177	$ 919,411
Administrative and general	46,655	31,463	119,418	101,826
Depreciation and amortization	33,604	33,503	100,216	100,834
Total costs and expenses	317,935	304,506	908,192	883,226
Gain (Loss) on Sale of Assets and Asset Impairment Charges	29,869	19,230	38,842	33,550
Operating Income (Loss)	50,870	51,508	107,827	69,735
Nonoperating Income (Expense)	(2,454)	(4,985)	(505)	(16,471)
Income Tax Expense (Benefit)	(15,610)	(15,984)	(34,985)	(21,306)
Equity in Earnings (Losses) of 50% or Less Owned Companies, Net of Tax	972	230	2,681	7,071
Net Income (Loss)	33,778	30,769	75,018	28,704
SES Business [Member]
Nonoperating Income (Expense)				(1,537)
Income Tax Expense (Benefit)				538
Net Income (Loss)				(999)
SEI [Member]
Nonoperating Income (Expense)				(143)
Income Tax Expense (Benefit)				50
Net Income (Loss)				(93)
Era Group [Member]
Operating Revenues				22,892
Operating Expenses				14,076
Administrative and general				2,653
Depreciation and amortization				3,875
Total costs and expenses				20,604
Gain (Loss) on Sale of Assets and Asset Impairment Charges				548
Operating Income (Loss)				2,836
Nonoperating Income (Expense)				(1,316)
Income Tax Expense (Benefit)				(10,818)
Equity in Earnings (Losses) of 50% or Less Owned Companies, Net of Tax				65
Net Income (Loss)				$ (9,233)