Subsequent Event - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
May 03, 2017	Mar. 31, 2017	Mar. 31, 2016
Subsequent Event [Line Items]
Special cash dividend payable (USD per share)		$ 0.3125	$ 0.28
Aggregate amount of special cash dividend		$ (27)	$ (24)
Subsequent Event
Subsequent Event [Line Items]
Special cash dividend payable (USD per share)	$ 1.50
Aggregate amount of special cash dividend	$ (132)

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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