Deposits - Deposits (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Deposits [Abstract]
U.S. offices	$ 208,102	$ 150,759
Non-U.S. offices	53,132	39,260
Total	$ 261,234	$ 190,019

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

Name:	us-gaap_DepositsDomestic
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(a))
-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12(a))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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Balance Type:	credit
Period Type:	instant