Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands		6 Months Ended
	Aug. 03, 2015 $ / shares shares	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($)	Dec. 31, 2014 $ / shares shares
Correction of Operating and Investing Cash Flows for the Three Months Ended March 31, 2014
Common stock, shares authorized | shares		100,000,000		100,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.01		$ 0.01
Change in operating assets and liabilities:
accounts receivable - JIB and other		$ 22,617	$ (1,557)
Net cash provided by operating activities		138,650	173,561
Investment in property and equipment		(190,278)	(275,547)
Net cash used in investing activities		$ (149,994)	(128,028)
As Previously Reported
Change in operating assets and liabilities:
accounts receivable - JIB and other			1,929
Net cash provided by operating activities			177,047
Investment in property and equipment			(279,033)
Net cash used in investing activities			$ (131,514)
Subsequent event
Correction of Operating and Investing Cash Flows for the Three Months Ended March 31, 2014
Stock split ratio	0.10
Common stock, shares authorized | shares	100,000,000
Common stock, par value (in dollars per share) | $ / shares	$ 0.01