Summary of Significant Accounting Policies (Basic and Diluted EPS Calculation for Continuing Operations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income from continuing operations	$ 441	$ 384	$ 480	$ 490	$ 380	$ 329	$ 429	$ 498	$ 1,795	$ 1,636	$ 1,471
Less: Net income attributable to non-controlling interests									27	37	32
Net income attributable to the Company									$ 1,768	$ 1,599	$ 1,439
Basic weighted average common shares outstanding (in shares)									519	531	545
Dilutive effect of potentially issuable common shares (in shares)									5	5	8
Dilutive weighted average common shares outstanding (in shares)									524	536	553
Average stock price used to calculate common stock equivalents (in dollars per share)									$ 63.51	$ 56.27	$ 51.15