Deposits - Noninterest and Interest-bearing (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
U.S. offices
Noninterest-bearing	$ 441,245	$ 437,558
Interest-bearing:
Demand	83,043	90,319
Savings	478,922	466,730
Time (included $8,589 and $7,501 at fair value)	82,263	86,301
Total interest-bearing deposits	644,228	643,350
Total deposits in U.S. offices	1,085,473us-gaap_DepositsDomestic	1,080,908us-gaap_DepositsDomestic
Non-U.S. offices
Noninterest-bearing	18,484	19,078
Interest-bearing
Demand	216,815	217,011
Savings	1,999	2,673
Time (included $2,361 and $1,306 at fair value)	45,116	43,757
Total interest-bearing deposits	263,930	263,441
Total deposits in non-U.S. offices	282,414us-gaap_DepositsForeign	282,519us-gaap_DepositsForeign
Total deposits	1,367,887us-gaap_Deposits	1,363,427us-gaap_Deposits
Estimate of Fair Value
Interest-bearing:
Time (included $8,589 and $7,501 at fair value)	8,589	7,501
Interest-bearing
Time (included $2,361 and $1,306 at fair value)	$ 2,361	$ 1,306

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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The aggregate of all domestic interest-bearing and noninterest-bearing deposit liabilities.

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The aggregate of all foreign interest-bearing and noninterest-bearing deposit liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-05(a))

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-Publisher FASB

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12(a))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Subparagraph a

-Article 9

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Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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Amount of foreign interest-bearing deposits held by the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

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Amount of interest-bearing domestic time deposits. Time deposits bear interest for a fixed, stated period of time and include certificate of deposits and individual retirement accounts.

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Amount of money in interest-bearing foreign accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits. Checking and negotiable order withdrawals (NOW) are the most common forms of demand deposits.

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Amount of interest-bearing savings deposit liabilities in foreign banking offices.

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Amount of interest-bearing time deposits in foreign banking offices. Time deposits bear interest for a fixed, stated period of time and include certificate of deposits and individual retirement accounts.

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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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Amount of foreign noninterest-bearing deposits held by the entity which may include demand deposits, checking, brokered and retail deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-05)

-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537907-122884

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 05

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