Description of Business and Basis of Presentation - Restatement Table - Consolidated Statement of Cash Flows (Details) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015		Jun. 30, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		$ 115,648		$ 101,881	[1]	$ (61,744)		$ 195,677	[1]
Depreciation and amortization		61,485	[2]	44,962	[1]	123,555	[2],[3]	85,857	[1]
Impairments		1,268	[2]	343	[1]	273,892	[2],[3]	1,533	[1],[4]
Deferred income taxes						1,288		2,218	[1]
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net						(114)		3,320	[1]
As Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		112,546		$ 97,746	[5]	198,512		$ 187,921	[5]
Depreciation and amortization	[2]	64,693				126,763	[3]
Impairments	[2]	1,268				9,490	[3]
Deferred income taxes						1,825
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net						287
Adjustments [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		3,102				(260,256)
Depreciation and amortization	[2]	(3,208)				(3,208)	[3]
Impairments	[2]	$ 0				264,402	[3]
Deferred income taxes						(537)
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net						$ (401)

[1] Financial information has been recast to include the financial position and results attributable to the DBJV system. See Note 1 and Note 2.

[2] “As Reported” amounts previously included as a component of Depreciation, amortization and impairments in WGP’s Original Filing.

[3] “As Reported” amounts previously included as a component of Depreciation, amortization and impairments in WGP’s Original Filing.

[4] Financial information has been recast to include the financial position and results attributable to the DBJV system. See Note 1 and Note 2.

[5] See Adjustments to Previously Issued Financial Statements in Note 1.