CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net income	$ 1,419,000	$ 49,238,000
Adjustments to reconcile net income to net cash provided from operating activities:
Deferred income tax expense	5,688,000	42,676,000
Depletion, depreciation and amortization and impairment	138,718,000	169,578,000
Exploration dry hole costs	0	2,000
Abandonment and impairment of unproved properties	12,659,000	11,773,000
Derivative fair value loss	61,731,000	14,009,000
Cash settlements on derivative financial instruments	24,834,000	8,925,000
Amortization of deferred financing costs and other	1,807,000	1,312,000
Deferred and stock-based compensation	14,112,000	18,527,000
Loss (gain) on the sale of assets	189,000	(23,000)
Changes in working capital:
Accounts receivable	134,006,000	53,913,000
Inventory and other	(4,763,000)	(5,294,000)
Accounts payable	(30,431,000)	47,453,000
Accrued liabilities and other	(99,275,000)	(41,517,000)
Net cash provided from operating activities	260,694,000	370,572,000
Investing activities:
Additions to natural gas and oil properties	(190,014,000)	(308,641,000)
Additions to field service assets	(576,000)	(239,000)
Acreage purchases	(23,646,000)	(25,355,000)
Proceeds from disposal of assets	332,000	40,000
Purchases of marketable securities held by the deferred compensation plan	(4,259,000)	(13,153,000)
Proceeds from the sales of marketable securities held by the deferred compensation plan	6,204,000	11,928,000
Net cash used in investing activities	(211,959,000)	(335,420,000)
Financing activities:
Borrowings on credit facilities	566,000,000	528,000,000
Repayments on credit facilities	(614,000,000)	(557,000,000)
Dividends paid	(5,023,000)	(4,971,000)
Taxes paid for shares withheld	(3,161,000)	(2,659,000)
Change in cash overdrafts	7,218,000	922,000
Proceeds from the sales of common stock held by the deferred compensation plan	174,000	635,000
Net cash used in financing activities	(48,792,000)	(35,073,000)
(Decrease) increase in cash and cash equivalents	(57,000)	79,000
Cash and cash equivalents at beginning of period	545,000	448,000
Cash and cash equivalents at end of period	$ 488,000	$ 527,000