Commitments and contingent liabilities - Summary of Off-Balance Sheet Credit Risks, Net of Participations (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Securities lending indemnifications, joint venture	$ 64,000	$ 62,000
Invested in reverse repurchase agreements
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Cash collateral invested in indemnified repurchase agreements	50,000	41,000
Lending commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risks	46,892	47,577
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risks	1,993	2,265
Off-balance sheet credit risks participations	126	154
Commercial letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risks	146	60
Securities lending indemnifications
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risks	$ 485,626	$ 469,121

Cash collateral invested in indemnified repurchase agreements

No definition available.

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- Definition

Off-balance sheet credit risks participations amount.

+ References

No definition available.

+ Details

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- Definition

This item represents securities lending indemnifications - joint venture

+ References

No definition available.

+ Details

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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