SUPPLEMENTAL INFORMATION ON OIL AND NATURAL GAS OPERATIONS - UNAUDITED (Tables)

12 Months Ended

Dec. 31, 2015

Net Costs Incurred on Unevaluated Properties

The following table discloses net costs incurred (evaluated) on our unevaluated properties located in the United States for the years indicated:

	Year Ended December 31,
Unevaluated oil and gas properties – United States:	2015			2014			2013
Net costs incurred (evaluated) during year:
Acquisition costs	$	(115,767	)	$	(42,384	)	$	30,271
Exploration costs	(16,315		)	(186,308		)	188,830
Capitalized interest	41,339			45,722			46,860
	$	(90,743	)	$	(182,970	)	$	265,961

Financial Data Associated with Unevaluated Costs

The following table discloses financial data associated with unevaluated costs (United States) at December 31, 2015:

	Balance as of		Net Costs Incurred During the Year Ended December 31,
	December 31, 2015		2015			2014			2013		2012 and prior
Acquisition costs	$	173,902	$	(33,623	)	$	(5,118	)	$	40,535	$	172,108
Exploration costs	148,518		41,936			42,899			42,186		21,497
Capitalized interest	117,623		20,257			23,538			24,162		49,666
Total unevaluated costs	$	440,043	$	28,570		$	61,319		$	106,883	$	243,271

Summary of Estimated Proved Oil and Natural Gas Reserve

The following table sets forth an analysis of the estimated quantities of net proved oil (including condensate), natural gas and NGL reserves, all of which are located onshore and offshore the continental United States. Estimated proved oil, natural gas and NGL reserves at December 31, 2015, 2014 and 2013 are prepared in accordance with the SEC’s rule, “Modernization of Oil and Gas Reporting,” using a historical 12-month average pricing assumption.

	Oil (MBbls)		NGLs (MBbls)		Natural Gas (MMcf)		Oil, Natural Gas and NGLs (MMcfe)
Estimated proved reserves as of December 31, 2012	44,918		18,066		395,374		773,285
Revisions of previous estimates	3,606		2,439		36,006		72,275
Extensions, discoveries and other additions	2,367		4,395		79,729		120,299
Sale of reserves	(170	)	—		(214	)	(1,235	)
Production	(6,894	)	(1,603	)	(50,129	)	(101,111	)
Estimated proved reserves as of December 31, 2013	43,827		23,297		460,766		863,513
Revisions of previous estimates	(624	)	(331	)	(4,631	)	(10,362	)
Extensions, discoveries and other additions	9,650		7,521		131,617		234,639
Sale of reserves	(4,888	)	(556	)	(46,483	)	(79,151	)
Production	(5,568	)	(2,114	)	(47,426	)	(93,515	)
Estimated proved reserves as of December 31, 2014	42,397		27,817		493,843		915,124
Revisions of previous estimates	(6,818	)	(20,777	)	(362,102	)	(527,675	)
Extensions, discoveries and other additions	862		11		1,499		6,738
Purchase of producing properties	685		1,808		26,136		41,095
Sale of reserves	(859	)	—		(1,061	)	(6,213	)
Production	(5,991	)	(2,401	)	(36,457	)	(86,809	)
Estimated proved reserves as of December 31, 2015	30,276		6,458		121,858		342,260
Estimated proved developed reserves:
as of December 31, 2013	27,920		11,569		246,946		483,885
as of December 31, 2014	22,957		13,743		249,924		470,118
as of December 31, 2015	21,734		4,784		90,262		249,366
Estimated proved undeveloped reserves:
as of December 31, 2013	15,907		11,728		213,820		379,628
as of December 31, 2014	19,440		14,074		243,919		445,006
as of December 31, 2015	8,542		1,674		31,596		92,894

Summary of Standardized Measure of Discounted Future Net Cash Flows

The following tables present the standardized measure of discounted future net cash flows related to estimated proved oil, natural gas and NGL reserves together with changes therein, including a reduction for estimated plugging and abandonment costs that are also reflected as a liability on the balance sheet at December 31, 2015. You should not assume that the future net cash flows or the discounted future net cash flows, referred to in the tables below, represent the fair value of our estimated oil, natural gas and NGL reserves. Prices are based on either the historical 12-month average price based on closing prices on the first day of each month, or prices defined by existing contractual arrangements. The 2015 average historical 12-month oil and natural gas prices, net of applicable differentials, were $51.16 per Bbl of oil, $16.40 per Bbl of NGLs and $2.19 per Mcf of natural gas. The 2014 average 12-month oil and natural gas prices, net of applicable differentials, were $89.46 per Bbl of oil, $36.79 per Bbl of NGLs and $3.68 per Mcf of natural gas. The 2013 average 12-month oil and natural gas prices, net of applicable differentials, were $102.21 per Bbl of oil, $37.59 per Bbl of NGLs and $3.66 per Mcf of natural gas. Future production and development costs are based on current costs with no escalations. Estimated future cash flows net of future income taxes have been discounted to their present values based on a 10% annual discount rate.

	Standardized Measure Year Ended December 31,
	2015			2014			2013
Future cash inflows	$	1,921,329		$	6,635,751		$	7,040,928
Future production costs	(651,396		)	(2,413,004		)	(2,062,657		)
Future development costs	(679,355		)	(1,511,687		)	(1,431,101		)
Future income taxes	—			(609,516		)	(884,637		)
Future net cash flows	590,578			2,101,544			2,662,533
10% annual discount	13,259			(682,752		)	(977,531		)
Standardized measure of discounted future net cash flows	$	603,837		$	1,418,792		$	1,685,002

	Changes in Standardized Measure Year Ended December 31,
	2015			2014			2013
Standardized measure at beginning of year	$	1,418,792		$	1,685,002		$	1,513,859
Sales and transfers of oil, natural gas and NGLs produced, net of production costs	(340,477		)	(486,232		)	(708,017		)
Changes in price, net of future production costs	(237,747		)	(864,118		)	229,425
Extensions and discoveries, net of future production and development costs	1,573			549,649			155,592
Changes in estimated future development costs, net of development costs incurred during the period	731,115			203,026			28,684
Revisions of quantity estimates	(1,458,652		)	(27,495		)	281,558
Accretion of discount	174,456			222,009			202,087
Net change in income taxes	325,768			209,323			(28,084		)
Purchases of reserves in-place	3,493			—			—
Sales of reserves in-place	—			(152,787		)	15,531
Changes in production rates due to timing and other	(14,484		)	80,415			(5,633		)
Net increase (decrease) in standardized measure	(814,955		)	(266,210		)	171,143
Standardized measure at end of year	$	603,837		$	1,418,792		$	1,685,002

United States [Member]

Financial Data Relative to Oil and Gas Producing Activities

The following table discloses certain financial data relative to our oil and gas producing activities located onshore and offshore in the continental United States:

	Year Ended December 31,
	2015			2014			2013
Oil and gas properties – United States, proved and unevaluated:
Balance, beginning of year	$	9,348,054		$	8,517,873		$	7,692,261
Costs incurred during the year (capitalized):
Acquisition costs, net of sales of unevaluated properties	(14,158		)	44,634			70,903
Exploratory costs	104,169			270,850			297,113
Development costs (1)	266,982			438,334			378,242
Salaries, general and administrative costs	27,984			33,975			32,815
Interest	41,339			45,722			46,860
Less: overhead reimbursements	(913		)	(3,334		)	(321		)
Total costs incurred during the year, net of divestitures	425,403			830,181			825,612
Balance, end of year	$	9,773,457		$	9,348,054		$	8,517,873
Accumulated DD&A:
Balance, beginning of year	$	(6,970,631	)	$	(5,908,760	)	$	(5,510,166	)
Provision for DD&A	(277,088		)	(335,987		)	(346,827		)
Write-down of oil and gas properties	(1,314,817		)	(351,192		)	—
Sale of proved properties	1,064			(374,692		)	(51,767		)
Balance, end of year	$	(8,561,472	)	$	(6,970,631	)	$	(5,908,760	)
Net capitalized costs – United States, proved and unevaluated	$	1,211,985		$	2,377,423		$	2,609,113
DD&A per Mcfe	$	3.19		$	3.59		$	3.43
(1) Includes capitalized asset retirement costs of ($43,901), ($20,305) and $54,737, respectively.
Costs incurred during the year (expensed):
Lease operating expenses	$	100,139		$	176,495		$	201,153
Transportation, processing and gathering expenses	58,847			64,951			42,172
Production taxes	6,877			12,151			15,029
Accretion expense	25,988			28,411			33,575
Expensed costs – United States	$	191,851		$	282,008		$	291,929

Canada [Member]

Financial Data Relative to Oil and Gas Producing Activities

The following table discloses certain financial data relative to our oil and gas activities located in Canada:

	Year Ended December 31,
	2015			2014		2013
Oil and gas properties – Canada:
Balance, beginning of year	$	36,579		$	10,583	$	—
Costs incurred during the year (capitalized):
Acquisition costs	(2,862		)	6,956		8,764
Exploratory costs	8,767			19,040		1,819
Total costs incurred during the year	5,905			25,996		10,583
Balance, end of year (fully evaluated at December 31, 2015 and unevaluated at December 31, 2014 and 2013)	$	42,484		$	36,579	$	10,583
Accumulated DD&A:
Balance, beginning of year	$	—		$	—	$	—
Foreign currency translation adjustment	5,146			$	—	—
Write-down of oil and gas properties	(47,630		)	$	—	—
Balance, end of year	$	(42,484	)	$	—	$	—
Net capitalized costs – Canada	$	—		$	36,579	$	10,583