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=6367179&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 holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Stockholders' Equity - Dividends (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended								12 Months Ended
	Feb. 06, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Cash dividends declared per share (in US$ per share)		$ 0.52	$ 0.52	$ 0.52	$ 0.52	$ 0.47	$ 0.47	$ 0.47	$ 0.43	$ 2.08	$ 1.84	$ 1.29
Dividends, Common Stock, Cash		$ 687	$ 685	$ 685	$ 685	$ 622	$ 625	$ 631	$ 587	$ 2,742	$ 2,465
Subsequent Event [Member]
Subsequent Event [Line Items]
Cash dividends declared per share (in US$ per share)	$ 0.57
Dividends Payable, Date to be Paid	Mar. 29, 2018
Dividends Payable, Date of Record	Mar. 16, 2018