INVESTMENT IN OIL AND GAS PROPERTIES - UNAUDITED (Tables)

12 Months Ended

Dec. 31, 2013

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,
	2013		2012			2011
Unevaluated oil and gas properties – United States:
Net costs incurred (evaluated) during year:
Acquisition costs	$	30,271	$	9,739			($2,397	)
Exploration costs		188,830		(1,209	)		(51,207	)
Capitalized interest		46,860		37,656			42,033
	$	265,961	$	46,186			($11,571	)

Oil and Gas Related Operating Costs Incurred During and Expensed

Costs incurred during the year (expensed):
Lease operating expenses	$	201,153	$	215,003	$	175,881
Transportation, processing and gathering expenses		42,172		21,782		8,958
Production taxes		15,029		10,015		9,380
Accretion expense		33,575		33,331		30,764
Expensed costs – United States	$	291,929	$	280,131	$	224,983

Financial Data Associated with Unevaluated Costs

The following table discloses financial data associated with unevaluated costs (United States and Canada) at December 31, 2013:

	Balance as of December 31, 2013		Net Costs Incurred During the Year Ended December 31,
			2013		2012		2011		2010 and prior
Acquisition costs	$	306,793	$	78,555	$	29,959	$	41,442	$	156,837
Exploration costs		305,422		248,846		56,033		499		44
Capitalized interest		112,124		39,846		32,755		20,501		19,022
Total unevaluated costs	$	724,339	$	367,247	$	118,747	$	62,442	$	175,903

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,
	2013			2012			2011
Oil and gas properties – United States, proved and unevaluated:
Balance, beginning of year	$	7,692,261		$	7,049,777		$	6,202,758
Costs incurred during the year (capitalized):
Acquisition costs, net of sales of unevaluated properties		70,903			102,807			270,354
Exploratory costs		297,113			81,458			84,199
Development costs (1)		378,242			395,555			426,355
Salaries, general and administrative costs		32,815			25,318			24,430
Interest		46,860			37,656			42,033
Less: overhead reimbursements		(321	)		(310	)		(352	)
Total costs incurred during the year, net of divestitures		825,612			642,484			847,019
Balance, end of year	$	8,517,873		$	7,692,261		$	7,049,777
Accumulated DD&A:
Balance, beginning of year	($	5,510,166	)	($	5,174,729	)	($	4,804,949	)
Provision for DD&A		(346,827	)		(341,096	)		(276,480	)
Sale of proved properties		(51,767	)		5,659			(93,300	)
Balance, end of year	($	5,908,760	)	($	5,510,166	)	($	5,174,729	)
Net capitalized costs – United States, proved and unevaluated	$	2,609,113		$	2,182,095		$	1,875,048
DD&A per Mcfe	$	3.43		$	3.69		$	3.45

(1) Includes capitalized asset retirement costs of $54,737, $95,293 and $96,386, respectively.

Canada [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 in Canada:

	Year Ended December 31,
	2013
Oil and gas properties – Canada, unevaluated:
Balance, beginning of year	$	—
Costs incurred during the year (capitalized):
Acquisition costs		8,764
Exploratory costs		1,819
Total costs incurred during the year		10,583
Balance, end of year, unevaluated	$	10,583