Description of Business and Basis of Presentation - Restatement Table - Consolidated Statement of Cash Flows (details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2015		Mar. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		$ (177,392)		$ 93,796	[1]
Impairments		272,624	[2],[3]	1,190
Deferred income taxes		3,283		993	[1]
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net		9,983		5,851	[1]
As Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		85,966		$ 90,175	[4]
Impairments	[2],[3]	8,222
Deferred income taxes		3,758
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net		10,552
Adjustments [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income (loss)		(263,358)
Impairments	[2],[3]	264,402
Deferred income taxes		(475)
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net		$ (569)

[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” amount previously included as a component of Depreciation, amortization and impairments in WGP’s Original Filing.

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

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