Debt and Interest Expense - Interest Expense Table (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015		Jun. 30, 2016	Jun. 30, 2015
Debt Instrument [Line Items]
Interest expense	[1]	$ 13,429	$ 27,604	[2]	$ 45,568	$ 50,566	[2]
Third Parties [Member]
Debt Instrument [Line Items]
Long-term debt		28,472	24,733		56,328	48,075
Amortization of debt issuance costs and commitment fees		1,900	1,374		3,495	2,666
Capitalized interest		(1,482)	(2,693)		(3,331)	(5,787)
Interest expense		28,890	23,414		56,492	44,954
Affiliates [Member]
Debt Instrument [Line Items]
Interest expense	[3]	(15,461)	4,190		(10,924)	5,612
Affiliates [Member] | Deferred Purchase Price Obligation - Anadarko [Member]
Debt Instrument [Line Items]
Interest expense, affiliate	[4]	(15,461)	4,190		(10,924)	5,610
Affiliates [Member] | Working Capital Facility [Member]
Debt Instrument [Line Items]
Interest expense, affiliate		$ 0	$ 0		$ 0	$ 2

[1] Includes affiliate (as defined in Note 1) amounts of $(15.5) million and $(10.9) million for the three and six months ended June 30, 2016, respectively, and $4.2 million and $5.6 million for the three and six months ended June 30, 2015, respectively. See Note 2 and Note 9.

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

[3] For the three and six months ended June 30, 2016, includes WES’s accretion revisions to the Deferred purchase price obligation - Anadarko (see Note 2 and Note 9) and for the three and six months ended June 30, 2015, includes interest expense recognized on the WGP WCF (see Note 9).

[4] See Note 2 for a discussion of the accretion and net present value of the Deferred purchase price obligation - Anadarko.