CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (in thousands) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income (loss)		$ (135,923)	$ (89,112)	$ 198,675	$ (134,585)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net (gain) loss on divestiture activity		(786)	1,895	(425,656)	131,565
Depletion, depreciation, amortization, and asset retirement obligation liability accretion		201,105	134,599	483,343	425,643
Abandonment and impairment of unproved properties		9,055	0	26,615	157
Stock-based compensation expense				17,680	16,160
Net derivative (gain) loss		178,026	80,599	249,304	(89,364)
Derivative settlement gain (loss)				(101,911)	29,402
Amortization of debt discount and deferred financing costs				11,542	12,478
Loss on extinguishment of debt		26,722	0	26,722	35
Deferred income taxes		(36,833)	(36,668)	60,672	(67,458)
Other, net				(2,084)	6,424
Net change working capital				(3,725)	40,153
Net cash provided by operating activities				541,177	370,610
Cash flows from investing activities:
Net proceeds from the sale of oil and gas properties				743,199	778,365
Capital expenditures				(1,032,588)	(624,969)
Acquisition of proved and unproved oil and gas properties				(24,571)	(87,389)
Net cash provided by (used in) investing activities				(313,960)	66,007
Cash flows from financing activities:
Proceeds from credit facility				0	406,000
Repayment of credit facility				0	(406,000)
Debt issuance costs related to credit facility				(4,771)	0
Net proceeds from Senior Notes				492,079	0
Cash paid to repurchase Senior Notes, including premium				(844,984)	(2,357)
Net proceeds from sale of common stock				1,881	1,738
Dividends paid				(5,584)	(5,563)
Other, net				(2,975)	(1,392)
Net cash used in financing activities				(364,354)	(7,574)
Net change in cash, cash equivalents, and restricted cash	[1]			(137,137)	429,043
Cash, cash equivalents, and restricted cash at beginning of period	[1]			313,943	12,372
Cash, cash equivalents, and restricted cash at end of period	[1]	176,806	441,415	176,806	441,415
Operating activities:
Cash paid for interest, net of capitalized interest				(124,435)	(124,443)
Net cash paid for income taxes				(9,085)	(2,800)
Investing activities:
Changes in capital expenditure accruals and other				19,811	2,788
Supplemental non-cash investing activities:
Carrying value of properties exchanged				95,121
Supplemental non-cash financing activities:
Non-cash loss on extinguishment of debt				6,334	22
Dividends declared, but not paid		$ 5,607	$ 5,581	$ 5,607	$ 5,581

[1] (1) Refer to Note 1 - Summary of Significant Accounting Policies for a reconciliation of cash, cash equivalents, and restricted cash reported to the amounts reported within the accompanying unaudited condensed consolidated balance sheets (“accompanying balance sheets”).