Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2016

Fair Value Measurements [Abstract]

Carrying Amount And Estimated Fair Values Of Financial Instruments

	June 30, 2016				December 31, 2015
	Carrying		Fair		Carrying		Fair
	Amount		Value		Amount		Value
	(in millions)
Cash and cash equivalents	$	998	$	998	$	15	$	15
Credit facility		–		–		116		116
Term loan facility due 2018		744		744		747		747
Term loan facility due 2020		1,180		1,180		–		–
Senior notes		3,844		3,580		3,842		2,651
Derivative instruments, net		(131)		(131)		(2)		(2)

Summary Of Assets And Liabilities Measured At Fair Value On Recurring Basis

	June 30, 2016
	Fair Value Measurements Using:
	Quoted Prices				Significant
	in Active		Significant Other		Unobservable
	Markets		Observable Inputs		Inputs		Assets (Liabilities)
	(Level 1)		(Level 2)		(Level 3)		at Fair Value
Fixed price swap assets	$	–	$	1	$	–	$	1
Two-way costless collars assets		–		–		12		12
Three-way costless collars assets		–		–		4		4
Basis swap assets		–		–		7		7
Fixed price swap liabilities		–		(41)		–		(41)
Two-way costless collars liabilities		–		–		(17)		(17)
Three-way costless collars liabilities		–		–		(6)		(6)
Basis swap liabilities		–		–		(8)		(8)
Sold call option liabilities		–		–		(75)		(75)
Interest rate swap liabilities		–		(8)		–		(8)
Total	$	–	$	(48)	$	(83)	$	(131)
	December 31, 2015
	Fair Value Measurements Using:
	Quoted Prices		Significant Other		Significant
	in Active Markets		Observable Inputs		Unobservable Inputs		Assets (Liabilities)
	(Level 1)		(Level 2)		(Level 3)		at Fair Value
Basis swap assets	$	–	$	–	$	3	$	3
Interest rate swap liabilities		–		(5)		–		(5)
Total	$	–	$	(5)	$	3	$	(2)

Reconciliations For Change In Net Fair Value Of Derivative Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Significant Unobservable Inputs (Level 3)

	For the three months ended				For the six months ended
	June 30,				June 30,
	2016		2015		2016		2015
	(in millions)
Balance at beginning of period	$	(35)	$	(8)	$	3	$	(8)
Total gains (losses):
Included in earnings		(37)		3		(71)		(3)
Purchases, issuances, and settlements:
Settlements		(11)		–		(15)		6
Transfers into/out of Level 3		–		–		–		–
Balance at end of period	$	(83)	$	(5)	$	(83)	$	(5)
Change in gains (losses) included in earnings relating to derivatives still held as of June 30	$	(48)	$	3	$	(86)	$	3