Supplemental Information on Oil and Gas Producing Activities (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2016

Supplemental Information on Oil and Gas Producing Activities (Unaudited)

Schedule of capitalized costs relating to oil and gas producing activities

	Year ended December 31,
(In thousands)	2015		2016
Proved properties	$	8,211,106		9,549,671
Unproved properties		1,996,081		2,331,173
		10,207,187		11,880,844
Accumulated depletion and depreciation		(1,415,005)		(2,089,500)
Net capitalized costs	$	8,792,182		9,791,344

Schedule of costs incurred in certain oil and gas activities

	Year ended December 31,
(In thousands)	2014		2015		2016
Acquisition costs:
Proved property	$	64,066		—		134,113
Unproved property		777,422		198,694		611,631
Development costs		1,536,193		1,039,301		1,000,903
Exploration costs		940,957		611,981		326,856
Total costs incurred	$	3,318,638		1,849,976		2,073,503

Schedule of results of operations (including discontinued operations) for oil and gas producing activities

	Year ended December 31,
(In thousands)	2014		2015		2016
Revenues	$	1,736,752		1,375,128		1,755,061
Operating expenses:
Production expenses		578,672		773,697		999,516
Exploration expenses		27,893		3,846		6,862
Depletion and depreciation		418,744		614,700		700,274
Impairment of unproved properties		15,198		104,321		162,935
Results of operations before income tax expense		696,245		(121,436)		(114,526)
Income tax (expense) benefit		(263,126)		45,497		43,334
Results of operations	$	433,119		(75,939)		(71,192)

Schedule of proved developed and undeveloped reserves

	Natural gas (Bcf)	NGLs (MMBbl)	Oil and condensate (MMBbl)		Equivalents (Bcfe)
Proved reserves:
December 31, 2013	6,753	137	10		7,632
Revisions	(1,025)	(6)	—	(a)	(1,054)
Extensions, discoveries and other additions	5,095	206	19		6,444
Purchases of reserves	29	—	—		29
Production	(317)	(7)	(1)		(368)
December 31, 2014	10,535	330	28		12,683
Revisions	(2,816)	176	(8)		(1,801)
Extensions, discoveries and other additions	2,253	97	8		2,878
Production	(439)	(16)	(2)		(545)
December 31, 2015	9,533	587	26		13,215
Revisions	(2,069)	275	3		(404)
Extensions, discoveries and other additions	1,990	99	9		2,637
Production	(505)	(27)	(2)		(676)
Purchases of reserves	475	23	2		624
Sales of reserves in place	(10)	—	—		(10)
December 31, 2016	9,414	957	38		15,386

^(a) Less than 1.0.

	Natural gas (Bcf)	NGLs (MMBbl)	Oil and condensate (MMBbl)	Equivalents (Bcfe)
Proved developed reserves:
December 31, 2014	3,285	80	6	3,803
December 31, 2015	3,627	360	8	5,838
December 31, 2016	4,426	401	13	6,914
Proved undeveloped reserves:
December 31, 2014	7,250	250	22	8,880
December 31, 2015	5,906	227	18	7,377
December 31, 2016	4,988	556	25	8,472

Schedule of standardized measure of discounted future net cash flows attributable to proved reserves

	Year ended December 31,
(in millions)	2014		2015		2016
Future cash inflows	$	63,632		35,179		36,800
Future production costs		(21,722)		(17,393)		(21,275)
Future development costs		(8,212)		(5,217)		(3,902)
Future net cash flows before income tax		33,698		12,569		11,623
Future income tax expense		(10,726)		(1,708)		(1,042)
Future net cash flows		22,972		10,861		10,581
10% annual discount for estimated timing of cash flows		(15,337)		(7,628)		(7,294)
Standardized measure of discounted future net cash flows	$	7,635		3,233		3,287

Schedule of weighted average prices used to estimate the Company's total equivalent reserves

December 31, 2014	$	5.02
December 31, 2015	$	2.66
December 31, 2016	$	2.39

Schedule of changes in standardized measure of discounted future net cash flow

	Year ended December 31,
(in millions)	2014		2015		2016
Sales of oil and gas, net of productions costs	$	(1,158)		(601)		(756)
Net changes in prices and production costs		(184)		(9,416)		(1,540)
Development costs incurred during the period		564		769		733
Net changes in future development costs		(102)		671		212
Extensions, discoveries and other additions		5,759		861		673
Acquisitions		42		—		66
Divestitures		—		—		(7)
Revisions of previous quantity estimates		(828)		(1,167)		461
Accretion of discount		600		1,132		363
Net change in income taxes		(2,198)		3,284		12
Other changes		630		65		(163)
Net increase (decrease)		3,125		(4,402)		54
Beginning of year		4,510		7,635		3,233
End of year	$	7,635		3,233		3,287