Revision of Previously Issued Financial Statements - Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income	$ 99	$ 196	$ 187	$ 366
Deferred income taxes	(1)	(86)	(1)	(74)
Increase (decrease) in payables	(29)	(5)	57	59
Increase (decrease) in accrued taxes	16	0	(22)	9
Changes in long-term liabilities	$ (6)	11	$ 1	13
As Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income		197		372
Deferred income taxes				(73)
Increase (decrease) in payables		(7)		55
Increase (decrease) in accrued taxes		1		10
Changes in long-term liabilities				9
Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income		(1)		(6)
Deferred income taxes				(1)
Increase (decrease) in payables		2		4
Increase (decrease) in accrued taxes		$ (1)		(1)
Changes in long-term liabilities				$ 4

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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