Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional gain included in income from discontinued operations, net of tax				$ 3,600
Income from discontinued operations before taxes		$ 3,300		3,100
Income from discontinued operations, net of tax	$ 0	1,876	$ 0	1,772
Income taxes from discontinued operations		1,400		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		140,900
Fair value of other contractual assets received		$ 32,500		$ 32,500