Variable Interest Entities - Summary of Assets and Liabilities Related to Consolidated Variable Interest Entities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013		Mar. 31, 2013
Variable Interest Entity [Line Items]
Interest bearing deposits with banks	$ 23,466		$ 19,614
Securities held-to-maturity	1,285		1,358
Other assets	7,567		8,140
Total assets	187,174	[1]	185,487	[1]	189,385
Other	3,907		3,558
Long-term debt	22,953		22,847
Total liabilities	170,507	[1]	169,023	[1]
Variable interest entities
Variable Interest Entity [Line Items]
Interest bearing deposits with banks	3		5
Securities held-to-maturity	180		200
Other assets	479		502
Total assets	662		707
Other	80		93
Long-term debt	92		92
Total liabilities	172		185
Asset-backed commercial paper conduits [Member]
Variable Interest Entity [Line Items]
Interest bearing deposits with banks	3		5
Securities held-to-maturity	180		200
Other assets	41		45
Total assets	224		250
Other	0		3
Total liabilities	0		3
Low Income Housing Limited Liability Partnership [Member]
Variable Interest Entity [Line Items]
Other assets	438		457
Total assets	438		457
Other	80		90
Long-term debt	92		92
Total liabilities	$ 172		$ 182

[1] The following table summarizes assets and liabilities related to our consolidated variable interest entities (“VIEs”) as of March 31, 2014 and December 31, 2013 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. Assets: Interest bearing deposits with banks, $3 million and $5 million, Securities held-to-maturity, $180 million and $200 million Other assets $479 million and $502 million. Total assets $662 million and $707 million respectively. Liabilities: Long-term debt $92 million and $92 million, Interest, taxes and other liabilities $80 million and $93 million. Total liabilities $172 million and $185 million, respectively.