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

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

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ 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=6367179&loc=d3e4304-108586

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Cash Dividends - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Apr. 11, 2016	Feb. 25, 2015
Dividends Payable [Line Items]
Dividends payable, amount per share				$ 0.46
Cash dividends paid	$ 173	$ 185
Subsequent Event [Member]
Dividends Payable [Line Items]
Dividends payable, amount per share			$ 0.05