Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations before taxes					$ 3,100
Income from discontinued operations, net of tax	$ 0	$ 0		$ 0	1,772
Income taxes from discontinued operations					1,300
Equitable Gas and Homeworks
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional cash proceeds as a result of post-closing purchase price adjustments			$ 7,400
Additional gain included in income from discontinued operations, net of tax					$ 3,600
Cash proceeds received			748,000
Fair value of select midstream assets received			140,900
Fair value of other contractual assets received			$ 32,500