Derivative Instruments- Offsetting (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Derivative [Line Items]
Asset derivatives fair value	$ 18,275	[1]	$ 20,288	[1]
Asset derivatives fair value, effect of master netting agreements	14,401	[2],[3]	15,806	[2],[3]
Asset derivatives fair value, fair value after effect of master netting agreements	3,874		4,482
Total derivatives not subject to netting arrangements	1,928		2,105
Securities Purchased under Agreements to Resell	13,394		10,180
Securities purchased under agreements to resell amount offset against collateral	1,238	[3],[4]	1,096	[3],[4]
Securities purchased under agreements to resell amount not offset against collateral	12,156		9,084
Fair value of financial and derivative asset	31,669		30,468
Fair value of financial and derivative asset amount offset against collateral	15,639	[3]	16,902	[3]
Fair value of financial and derivative asset amount not offset against collateral	16,030		13,566
Liability derivatives fair value	18,321	[1]	20,254	[1]
Liability derivatives fair value, effect of master netting agreements	13,856	[2],[5]	14,421	[2],[5]
Liability derivatives fair value, amount not offset against collateral	4,465		5,833
Total derivatives not subject to netting arrangements	1,384		2,248
Securities Sold under Agreements to Repurchase	11,130		10,528
Securities Sold Under Agreements To Repurchase Amount Offset Against Collateral	1,238	[5],[6]	1,096	[5],[6]
Securities Sold Under Agreements To Repurchase Amount Not Offset Against Collateral Abstract	9,892		9,432
Fair Value Of Financial and Derivative Liability	29,451		30,782
Fair Value Of Financial and Derivative Liability Amount Offset Against Collateral	15,094	[5]	15,517	[5]
Fair Value Of Financial and Derivative Liability Amount Not Offset Against Collateral	14,357		15,265
Derivatives subject to netting arrangements:
Derivative [Line Items]
Asset derivatives fair value	16,347		18,183
Asset derivatives fair value, effect of master netting agreements	14,401	[3]	15,806	[3]
Asset derivatives fair value, fair value after effect of master netting agreements	1,946		2,377
Liability derivatives fair value	16,937		18,006
Liability derivatives fair value, effect of master netting agreements	13,856	[5]	14,421	[5]
Liability derivatives fair value, amount not offset against collateral	3,081		3,585
Interest rate contracts | Derivatives subject to netting arrangements:
Derivative [Line Items]
Asset derivatives fair value	14,285		14,798
Asset derivatives fair value, effect of master netting agreements	12,810	[3]	13,231	[3]
Asset derivatives fair value, fair value after effect of master netting agreements	1,475		1,567
Liability derivatives fair value	14,741		14,914
Liability derivatives fair value, effect of master netting agreements	12,404	[5]	12,429	[5]
Liability derivatives fair value, amount not offset against collateral	2,337		2,485
Foreign exchange contracts | Derivatives subject to netting arrangements:
Derivative [Line Items]
Asset derivatives fair value	1,594		2,778
Asset derivatives fair value, effect of master netting agreements	1,363	[3]	2,294	[3]
Asset derivatives fair value, fair value after effect of master netting agreements	231		484
Liability derivatives fair value	1,547		2,292
Liability derivatives fair value, effect of master netting agreements	1,218	[5]	1,711	[5]
Liability derivatives fair value, amount not offset against collateral	329		581
Equity contracts | Derivatives subject to netting arrangements:
Derivative [Line Items]
Asset derivatives fair value	468		607
Asset derivatives fair value, effect of master netting agreements	228	[3]	281	[3]
Asset derivatives fair value, fair value after effect of master netting agreements	240		326
Liability derivatives fair value	649		800
Liability derivatives fair value, effect of master netting agreements	234	[5]	281	[5]
Liability derivatives fair value, amount not offset against collateral	$ 415		$ 519

[1] Fair values are on a gross basis, before consideration of master netting agreements, as required by ASC 815.

[2] Master netting agreements are reported net of cash collateral received and paid of $1,119 million and $574 million, respectively, at March 31, 2014, and $1,841 million and $456 million, respectively, at Dec. 31, 2013.

[3] Includes the effect of netting agreements and net cash collateral paid. The offset related to the over-the-counter derivatives was allocated to the various types of derivatives based on the net positions.

[4] Offsetting of reverse repurchase agreements relates to our involvement in the Fixed Income Clearing Corporation, where we settle government securities transactions on a net basis for payment and delivery through the Fedwire system.

[5] Includes the effect of netting agreements and net cash collateral received. The offset related to the over-the-counter derivatives was allocated to the various types of derivatives based on the net positions.

[6] Offsetting of repurchase agreements relates to our involvement in the Fixed Income Clearing Corporation, where we settle government securities transactions on a net basis for payment and delivery through the Fedwire system.