Derivatives (Tables)

3 Months Ended

Mar. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivatives as they appear on the balance sheet [Table Text Block]

The following tables present the gross fair values of derivative instruments and the reported net amounts along with where they appear on the consolidated balance sheets.

	March 31, 2018
(In millions)	Asset		Liability		Net Asset (Liability)			Balance Sheet Location
Not Designated as Hedges
Commodity	$	3	$	—	$	3		Other current assets
Commodity	—		183		$	(183	)	Other current liabilities
Commodity	—		4		(4		)	Deferred credits and other liabilities
Total Not Designated as Hedges	$	3	$	187	$	(184	)

	December 31, 2017
(In millions)	Asset		Liability		Net Asset (Liability)			Balance Sheet Location
Not Designated as Hedges
Commodity	$	—	$	138	$	(138	)	Other current liabilities
Commodity	—		2		(2		)	Deferred credits and other liabilities
Total Not Designated as Hedges	$	—	$	140	$	(140	)

Forward Starting Interest Rate Swap Agreements by Maturity [Table Text Block]

The following table presents, by maturity date, information about our forward starting interest rate swap agreements, including the rate, which were terminated in the third quarter of 2017.

	March 31, 2017
	Aggregate Notional Amount		Weighted Average, LIBOR
Maturity Date	(in millions)		Fixed Rate
March 15, 2018	$	750	1.57	%

Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The following table sets forth the net impact of the terminated forward starting interest rate swap derivatives de-designated as cash flow hedges on other comprehensive income (loss).

	Three Months Ended March 31,
(In millions)	2018		2017
Interest Rate Swaps
Beginning balance	$	—	$	60
Change in fair value recognized in other comprehensive income	—		1
Reclassification from other comprehensive income	—		—
Ending balance	$	—	$	61

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

The following table sets forth outstanding derivative contracts as of March 31, 2018 and the weighted average prices for those contracts:

Crude Oil
	2018			2019				2020
	Second Quarter	Third Quarter	Fourth Quarter	First Quarter	Second Quarter	Third Quarter	Fourth Quarter	Full Year
Three-Way Collars
Volume (Bbls/day)	85,000	95,000	95,000	40,000	40,000	10,000	10,000	—
Weighted average price per Bbl:
Ceiling	$56.38	$57.65	$57.65	$66.46	$66.46	$70.00	$70.00	—
Floor	$51.65	$52.11	$52.11	$53.50	$53.50	$52.00	$52.00	—
Sold put	$45.00	$45.21	$45.21	$46.25	$46.25	$45.00	$45.00	—
Swaps
Volume (Bbls/day)	20,000	—	—	—	—	—	—	—
Weighted average price per Bbl	$55.12	—	—	—	—	—	—	—
Basis Swaps (a)
Volume (Bbls/day)	5,000	10,000	10,000	10,000	10,000	10,000	10,000	5,000
Weighted average price per Bbl	$(0.60)	$(0.67)	$(0.67)	$(0.82)	$(0.82)	$(0.82)	$(0.82)	$(0.25)

^(a)  The basis differential price is between WTI Midland and WTI Cushing.

Natural Gas
	2018
	Second Quarter	Third Quarter	Fourth Quarter
Three-Way Collars
Volume (MMBtu/day)	160,000	160,000	160,000
Weighted average price per MMBtu:
Ceiling	$3.61	$3.61	$3.61
Floor	$3.00	$3.00	$3.00
Sold put	$2.50	$2.50	$2.50