Stockholders' Equity 1 (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Cash dividends
Declaration date	May 02, 2018	May 09, 2017
Dividend per share (in dollars per share)	$ 0.255	$ 0.255
Record date	May 17, 2018	May 25, 2017
Total amount	$ 107	$ 107
Payment date	Jun. 05, 2018	Jun. 13, 2017

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

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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-Paragraph 1
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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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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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