Consolidated Statements of Changes in Equity (Parenthetical) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Income taxes effect on net unrealized (losses) gains on securities available for sale	$ 24	$ 93
Income taxes effect on net unrealized gains (losses) on derivative financial instruments	(16)	32
Income taxes effect on foreign currency translation adjustments	8	3
Income taxes effect on net pension and postretirement benefit costs	$ 4	$ 6
Cash dividends declared on common shares (in usd per share)	$ 0.275	$ 0.245
Series A Preferred Stock [Member]
Cash dividends declared on Preferred Stock (in usd per share)	1.9375	$ 5.8125
Series C Preferred Stock [Member]
Cash dividends declared on Preferred Stock (in usd per share)	0.539063
Series D Preferred Stock [Member]
Cash dividends declared on Preferred Stock (in usd per share)	37.5
Series E Preferred Stock [Member]
Cash dividends declared on Preferred Stock (in usd per share)	$ 1.161199

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)
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683

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