Discontinued Operations Discontinued Operations Summary of Income Statement Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue									$ 87,534	$ 176,761	$ 155,664
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax									160,612	0	0
Discontinued Operation Transaction Expenses									11,000
Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Taxes Net of Transaction Costs									151,550	0	0
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax									156,025	13,177	3,494
Discontinued Operation, Tax Effect of Discontinued Operation									83,614	5,216	1,497
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	1,639	(55)	69,312	1,515	1,140	3,448	1,491	1,882	72,411	7,961	1,997
Comprehensive income attributable to noncontrolling interests									(236)	(1,217)	(590)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	1,639	(55)	69,617	1,023	1,275	2,963	1,445	1,121	72,224	6,804	1,491
Ecova [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation Transaction Expenses									9,062	0	0
Comprehensive income attributable to noncontrolling interests									$ (187)	$ (1,157)	$ (506)