v3.3.0.814
Collateral (Detail) - USD ($)
$ in Millions
Sep. 30, 2015
Sep. 30, 2014
Settlement Guarantee Management [Abstract]    
Cash equivalents $ 1,023 $ 961
Pledged securities at market value 154 148
Letters of credit 1,178 1,242
Guarantees 971 1,554
Total $ 3,326 $ 3,905