Supplemental Equity and Comprehensive Income Information (Details 7) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Dec. 31, 2013	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Supplemental Equity and Comprehensive Income Information
Dividends declared in current period (in dollars per share)	$ 0.855						$ 3.395
Dividends paid in current period (in dollars per share)		$ 0.855	$ 0.855	$ 0.635	$ 2.565	$ 1.905	$ 2.54
Increase of Current Liabilities due to dividend declared but not paid	$ 567						$ 567