Derivative Instruments- Offsetting (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Derivative Asset [Abstract]
Asset derivatives fair value	$ 24,550	[1]	$ 24,658	[1]
Derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	17,874	[2],[3]	18,347	[2],[3]
Derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	6,676		6,311
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	489		590
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet cash collateral received	0		0
Derivative assets after impact of netting arrangements and collateral agreements, net amount	6,187		5,721
Total derivatives not subject to netting arrangements	4,064		3,607
Reverse repurchase agreements, gross assets recognized	20,750		11,634
Reverse repurchase agreements subject to netting arrangements, gross amounts offset in the balance sheet	2,020	[2],[4]	434	[2],[4]
Reverse repurchase agreements after impact of netting arrangements, net assets recognized on the balance sheet	18,730		11,200
Reverse repurchase agreements subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	18,728		11,198
Reverse repurchase agreements subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral received	0		0
Reverse repurchase agreements, net amount	2		2
Securities borrowing, gross assets recognized	9,252		9,033
Securities borrowing after impact of netting arrangements, net assets recognized on the balance sheet	9,252		9,033
Securities borrowing subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	8,952		8,733
Securities borrowing after impact of netting arrangements and collateral agreements, net amount	300		300
Fair value of financial and derivative assets, gross assets recognized	54,552		45,325
Fair value of financial and derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	19,894	[2]	18,781	[2]
Fair value of financial and derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	34,658		26,544
Fair value of financial and derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	28,169		20,521
Fair value of financial and derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral received	0		0
Fair value of financial and derivative assets after impact of netting arrangements and collateral agreements, net amount	6,489		6,023
Derivative Liability [Abstract]
Liability derivatives fair value	24,306	[1]	25,017	[1]
Derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	16,999	[3],[5]	17,797	[3],[5]
Derivative liability after impact of netting arrangements, net liabilities recognized on the balance sheet	7,307		7,220
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	2,527		2,464
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Derivative liabilities after impact of netting arrangements and collateral agreements, net amount	4,780		4,756
Total derivatives not subject to netting arrangements	3,779		3,411
Repurchase agreements, gross liabilities recognized	7,743		9,160
Repurchase agreements subject to netting arrangements, gross amounts offset in the balance sheet	2,020	[5],[6]	434	[5],[6]
Repurchase agreements after impact of netting arrangements, net liabilities recognized on the balance sheet	5,723		8,726
Repurchase agreements subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	5,721		8,722
Repurchase agreements subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Repurchase agreements, net amount	2		4
Securities lending, gross liabilities recognized	2,142		2,571
Securities lending after impact of netting arrangements, net liabilities recognized on the balance sheet	2,142		2,571
Securities lending subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	2,061		2,494
Securities lending after impact of netting arrangements and collateral agreements, net amount	81		77
Fair value of financial and derivative liabilities, gross liabilities recognized	34,191		36,748
Fair value of financial and derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	19,019	[5]	18,231	[5]
Fair value of financial and derivative liabilities after impact netting arrangements, net liabilities recognized on the balance sheet	15,172		18,517
Fair value of financial and derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	10,309		13,680
Fair value of financial and derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Fair value of financial and derivative liabilities after impact of netting arrangements and collateral agreements, net amount	4,863		4,837
Derivatives subject to netting arrangements:
Derivative Asset [Abstract]
Asset derivatives fair value	20,486		21,051
Derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	17,874	[2]	18,347	[2]
Derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	2,612		2,704
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	489		590
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet cash collateral received	0		0
Derivative assets after impact of netting arrangements and collateral agreements, net amount	2,123		2,114
Derivative Liability [Abstract]
Liability derivatives fair value	20,527		21,606
Derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	16,999	[5]	17,797	[5]
Derivative liability after impact of netting arrangements, net liabilities recognized on the balance sheet	3,528		3,809
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	2,527		2,464
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Derivative liabilities after impact of netting arrangements and collateral agreements, net amount	1,001		1,345
Interest rate contracts | Derivatives subject to netting arrangements:
Derivative Asset [Abstract]
Asset derivatives fair value	15,004		15,457
Derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	13,365	[2]	13,942	[2]
Derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	1,639		1,515
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	399		408
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet cash collateral received	0		0
Derivative assets after impact of netting arrangements and collateral agreements, net amount	1,240		1,107
Derivative Liability [Abstract]
Liability derivatives fair value	16,238		16,884
Derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	13,836	[5]	14,467	[5]
Derivative liability after impact of netting arrangements, net liabilities recognized on the balance sheet	2,402		2,417
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	2,069		1,815
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Derivative liabilities after impact of netting arrangements and collateral agreements, net amount	333		602
Foreign exchange contracts | Derivatives subject to netting arrangements:
Derivative Asset [Abstract]
Asset derivatives fair value	5,245		5,291
Derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	4,391	[2]	4,246	[2]
Derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	854		1,045
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	90		176
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet cash collateral received	0		0
Derivative assets after impact of netting arrangements and collateral agreements, net amount	764		869
Derivative Liability [Abstract]
Liability derivatives fair value	3,954		4,241
Derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	3,044	[5]	3,149	[5]
Derivative liability after impact of netting arrangements, net liabilities recognized on the balance sheet	910		1,092
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	267		399
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Derivative liabilities after impact of netting arrangements and collateral agreements, net amount	643		693
Equity contracts | Derivatives subject to netting arrangements:
Derivative Asset [Abstract]
Asset derivatives fair value	237		303
Derivative assets subject to netting arrangements, gross amounts offset in the balance sheet	118	[2]	159	[2]
Derivative assets after impact of netting arrangements, net assets recognized on the balance sheet	119		144
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	0		6
Derivative assets subject to collateral agreements, gross amounts not offset in the balance sheet cash collateral received	0		0
Derivative assets after impact of netting arrangements and collateral agreements, net amount	119		138
Derivative Liability [Abstract]
Liability derivatives fair value	335		481
Derivative liabilities subject to netting arrangements, gross amounts offset in the balance sheet	119	[5]	181	[5]
Derivative liability after impact of netting arrangements, net liabilities recognized on the balance sheet	216		300
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, financial instruments	191		250
Derivative liabilities subject to collateral agreements, gross amounts not offset in the balance sheet, cash collateral pledged	0		0
Derivative liabilities after impact of netting arrangements and collateral agreements, net amount	$ 25		$ 50

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

[2] 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.

[3] aster netting agreements includes cash collateral received and paid of $1,591 million and $716 million, respectively, at March 31, 2015, and $1,589 million and $1,039 million, respectively, at Dec. 31, 2014.

[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 paid. 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.