Receivables from and Payables to Brokerage Clients (Summary of Receivables from and Payables to Brokerage Clients) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Receivables from and Payables to Brokerage Clients [Abstract]
Margin loans, net of allowance for doubtful accounts	$ 15,257	$ 15,818
Other brokerage receivables	1,898	1,495
Receivables from brokerage clients — net	17,155	17,313	[1]
Interest-bearing payables	28,336	26,584
Non-interst-bearing payables	7,558	6,601
Payables to brokerage clients	$ 35,894	$ 33,185	[1]

[1] Adjusted for the retrospective adoption of ASU 2015-03. See New Accounting Standards in Note 2 for additional information.