CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities:
Net (loss) income	$ (1,746,481,000)	$ 333,146,000	$ (521,388,000)
Adjustments to reconcile net (loss) income to net cash provided from operating activities:
Deferred income tax benefit	(30,489,000)	(251,043,000)	(280,848,000)
Depletion, depreciation and amortization and impairment of proved properties	658,081,000	688,671,000	567,142,000
Impairment of goodwill	1,641,197,000	0	0
Exploration dry hole and impairment costs	4,000	9,172,000	18,000
Abandonment and impairment of unproved properties	514,994,000	269,725,000	30,076,000
Derivative fair value loss (income)	51,192,000	(213,350,000)	261,391,000
Cash settlements on derivative financial instruments	(131,522,000)	13,117,000	347,336,000
Allowance for bad debt	(1,000,000)	1,550,000	800,000
Amortization of deferred financing costs, loss on extinguishment of debt and other	2,515,000	5,445,000	7,170,000
Deferred and stock-based compensation	29,757,000	30,706,000	74,685,000
Loss (gain) on the sale of assets	10,666,000	(23,716,000)	7,074,000
Changes in working capital:
Accounts receivable	(142,381,000)	(102,866,000)	(20,586,000)
Inventory and other	138,000	(2,979,000)	6,220,000
Accounts payable	(4,274,000)	45,912,000	(27,259,000)
Accrued liabilities and other	138,293,000	12,764,000	(64,763,000)
Net cash provided from operating activities	990,690,000	816,254,000	387,068,000
Investing activities:
Additions to natural gas and oil properties	(960,916,000)	(1,148,613,000)	(466,252,000)
Additions to field service assets	(1,477,000)	(5,710,000)	(3,052,000)
Acreage purchases	(60,603,000)	(58,213,000)	(43,482,000)
MRD Merger, net of cash acquired	0	0	7,180,000
Proceeds from disposal of assets	324,549,000	72,468,000	193,755,000
Purchases of marketable securities held by the deferred compensation plan	(46,177,000)	(88,167,000)	(37,019,000)
Proceeds from the sales of marketable securities held by the deferred compensation plan	49,190,000	89,178,000	40,035,000
Net cash used in investing activities	(695,434,000)	(1,139,057,000)	(308,835,000)
Financing activities:
Borrowings on credit facilities	2,070,000,000	2,041,000,000	2,274,000,000
Repayments on credit facilities	(2,338,000,000)	(1,712,000,000)	(1,487,000,000)
Repayment of senior or senior subordinated notes	0	(500,000)	(273,012,000)
Dividends paid	(19,940,000)	(19,839,000)	(16,682,000)
Debt issuance costs	(8,220,000)	(403,000)	(6,342,000)
Taxes paid for shares withheld	(3,183,000)	(6,983,000)	(3,849,000)
Change in cash overdrafts	(5,563,000)	17,180,000	18,393,000
Proceeds from the sales of common stock held by the deferred compensation plan	9,747,000	4,482,000	13,102,000
Net cash (used in) provided from financing activities	(295,159,000)	322,937,000	(78,390,000)
Increase (decrease) in cash and cash equivalents	97,000	134,000	(157,000)
Cash and cash equivalents at beginning of year	448,000	314,000	471,000
Cash and cash equivalents at end of year	545,000	448,000	314,000
MRD
Adjustments to reconcile net (loss) income to net cash provided from operating activities:
Abandonment and impairment of unproved properties	436,000,000
Financing activities:
Repayments on credit facilities	$ 0	$ 0	$ (597,000,000)