Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income taxes effect on net unrealized (losses) gains on securities available for sale	$ 33	$ 17
Income taxes effect on net unrealized gains (losses) on derivative financial instruments	19	(1)
Income taxes effect on foreign currency translation adjustments	(8)	(4)
Income taxes effect on net pension and postretirement benefit costs	1	2
Cash dividends declared on common shares, per share	$ 0.065	$ 0.055
Retained Earnings [Member]
Cash dividends declared on common shares, per share	$ 0.065	$ 0.055
Accumulated Other Comprehensive Income (Loss) [Member]
Income taxes effect on net unrealized (losses) gains on securities available for sale	33	17
Income taxes effect on net unrealized gains (losses) on derivative financial instruments	19	(1)
Income taxes effect on foreign currency translation adjustments	(8)	(4)
Income taxes effect on net pension and postretirement benefit costs	$ 1	$ 2
Series A Preferred Stock [Member] \| Retained Earnings [Member]
Cash dividends declared on Preferred Stock, per share	$ 1.9375	$ 1.9375

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-SubTopic 10

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