Stockholders' Equity 1 (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Cash dividends
Declaration date	May 09, 2017	May 04, 2016
Dividend per share (in dollars per share)	$ 0.255	$ 0.255
Record date	May 25, 2017	May 26, 2016
Total amount	$ 107	$ 107
Payment date	Jun. 13, 2017	Jun. 14, 2016

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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Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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