Discontinued Operations Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		24 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Jun. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of Ecova			$ 0	$ 710
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	$ 0	$ 289	$ 0	485
Ecova [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Disposition Contract Price						$ 335,000
Escrow Receivable					$ (13,800)
Proceeds from Divestiture of Businesses					143,700
Gain (Loss) on Disposal of Discontinued Operation, Net of Tax					$ 74,800
Gain on sale of Ecova		547		710
Transaction Expenses and Accelerated Employee Benefits		24		24
Gain on Sale of Ecova, Net of Transaction Expenses		523		686
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax		523		686
Discontinued Operation, Tax Effect of Discontinued Operation		234		201
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent		$ 289		$ 485