Earnings Per Share (Details) - USD ($) $ in Millions			3 Months Ended		9 Months Ended
	May. 27, 2015	May. 26, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2015	Oct. 20, 2014	Feb. 15, 2013
Anti-dilutive securities excluded from the computation of earnings per common share
Amount authorized under stock repurchase program							$ 5,000	$ 5,000	$ 1,500
Payment for shares repurchased on the open market					$ 1,200	$ 250
Shares repurchased					21,000,000	5,000,000
Earnings allocable to participating securities - Basic (in dollars)			$ 7	$ 3	$ 18	$ 14
Earnings allocable to participating securities - Diluted (in dollars)			$ 7	$ 3	$ 18	$ 14
Morgan Stanley & Co. LLC
Anti-dilutive securities excluded from the computation of earnings per common share
Amount authorized under stock repurchase program		$ 5,000
Payment for shares repurchased on the open market		$ 5,000
Shares repurchased	68,000,000	68,000,000	5,000,000
Percentage of initial delivery of shares		90.00%
RSAs & RSUs
Anti-dilutive securities excluded from the computation of earnings per common share
Anti-dilutive securities excluded from the computation of earnings per common share (in shares)			3,000,000	4,000,000	3,000,000	4,000,000