CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash Flows From Operating Activities
Net income	$ 194,190	$ 127,515
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	226,080	180,458
Deferred income taxes	129,515	84,961
Loss on derivatives, net of settlement	61,900	30,800
Stock-based compensation	4,490	2,994
Other	508	(476)
Change in assets and liabilities:
Accounts receivable	(78,154)	(9,689)
Inventories	564	(1,944)
Accounts payable	94,346	7,312
Taxes payable	(12,863)	(14,177)
Interest payable	(9,512)	(7,245)
Advances from partners	56	(44,408)
Other assets and liabilities	(2,254)	16,037
Net cash provided by operating activities	608,866	372,138
Cash Flows From Investing Activities
Capital investments	(533,787)	(483,634)
Proceeds from sale of property and equipment	16,794
Transfers from restricted cash		1,434
Other	1,309	1,038
Net cash used in investing activities	(515,684)	(481,162)
Cash Flows From Financing Activities
Payments on revolving long-term debt	(1,131,300)	(369,700)
Borrowings under revolving long-term debt	1,008,600	404,800
Change in bank drafts outstanding	19,388	33,046
Proceeds from exercise of common stock options	5,983	4,799
Net cash (used in) provided by financing activities	(97,329)	72,945
Effect of exchange rate changes on cash	(72)	4
Decrease in cash and cash equivalents	(4,219)	(36,075)
Cash and cash equivalents at beginning of year	22,938	53,583
Cash and cash equivalents at end of period	$ 18,719	$ 17,508