Derivative instruments - Contracts Falling under Early Termination Provisions (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Credit Derivatives [Line Items]
Aggregate fair value of OTC derivatives in net liability positions	$ 4,790	$ 5,235
Collateral posted	5,216	5,568
A3 \| A-
Credit Derivatives [Line Items]
Aggregate fair value of OTC derivatives in net liability positions	45	79
Baa2 \| BBB
Credit Derivatives [Line Items]
Aggregate fair value of OTC derivatives in net liability positions	465	813
Ba1 \| BB+ and lower
Credit Derivatives [Line Items]
Aggregate fair value of OTC derivatives in net liability positions	$ 2,597	$ 2,859

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

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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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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

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