v3.4.0.3
Equity Method Investments (Narratives) (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Dec. 31, 2015
Equity Method Investments      
Equity method investment $ 3,257   $ 3,144
Income (loss) from equity method investments 15 $ 38  
MUMSS      
Equity Method Investments      
Income (loss) from equity method investments $ 34 $ 69  
Percent ownership 40.00% 40.00%  
MUMSS | MUFG      
Equity Method Investments      
Voting interest held by noncontrolling interest 60.00% 60.00%