Fair Value Measurements and Disclosures (Tables)

9 Months Ended

Sep. 30, 2015

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

Measurement information for assets and liabilities that are measured at fair value on a recurring basis was as follows: 

	Fair Value Measurements Using
	Quoted Prices in  Active Markets (Level 1) (1)			Significant Other Observable Inputs (Level 2) (2)			Significant Unobservable Inputs (Level 3) (3)		Adjustment (4)			Fair Value Measurement
(millions)
September 30, 2015
Financial Assets
Mutual Fund Investments	$	106		$	—		$	—	$	—		$	106
Commodity Derivative Instruments	—			759			—		(5		)	754
Financial Liabilities
Commodity Derivative Instruments	—			(11		)	—		5			(6		)
Portion of Deferred Compensation Liability Measured at Fair Value	(111		)	—			—		—			(111		)
December 31, 2014
Financial Assets
Mutual Fund Investments	$	111		$	—		$	—	$	—		$	111
Commodity Derivative Instruments	—			890					—			890
Financial Liabilities
Commodity Derivative Instruments	—			—			—		—			—
Portion of Deferred Compensation Liability Measured at Fair Value	(134		)	—			—		—			(134		)

⁽¹⁾  Level 1 measurements are fair value measurements which use quoted market prices (unadjusted) in active markets for identical assets or liabilities. We use Level 1 inputs when available as Level 1 inputs generally provide the most reliable evidence of fair value.

⁽²⁾  Level 2 measurements are fair value measurements which use inputs, other than quoted prices included within Level 1, which are observable for the asset or liability, either directly or indirectly.

⁽³⁾  Level 3 measurements are fair value measurements which use unobservable inputs.

⁽⁴⁾  Amount represents the impact of netting provisions within our master agreements that allow us to net cash settle asset and liability positions with the same counterparty.

Fair Value Measurements, Nonrecurring

Asset Impairments Information about impaired assets is as follows:

	Fair Value Measurements Using
Description	Quoted Prices in  Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Net Book Value (1)		Total Pre-tax (Non-cash) Impairment Loss
millions
Three Months Ended September 30, 2015
Impaired Oil and Gas Properties	$	—	$	—	$	—	$	—	$	—
Three Months Ended September 30, 2014
Impaired Oil and Gas Properties	—		—		9		42		33
Nine Months Ended September 30, 2015
Impaired Oil and Gas Properties	$	—	$	—	$	—	$	43	$	43
Nine Months Ended September 30, 2014
Impaired Oil and Gas Properties	—		—		23		187		164

⁽¹⁾ Amount represents net book value at the date of assessment.

Additional fair value disclosures

Fair value information regarding our debt is as follows:

	September 30, 2015				December 31, 2014
(millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Total Debt, Net of Unamortized Discount and Premium (1)	$	7,666	$	7,497	$	5,758	$	6,179

⁽¹⁾  Excludes capital lease obligations.