Derivative Instruments - Fair value and notional amount of derivatives (Details) - USD ($) $ in Millions		Sep. 30, 2023	Dec. 31, 2022
Derivative offsetting
Derivative assets subject to master netting agreements		$ 192	$ 147
Derivative liabilities subject to master netting agreements		$ 114	$ 73
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Other assets	Other assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other liabilities	Other liabilities
Not designated as hedging instrument
Derivative [Line Items]
Asset derivatives - fair value		$ 192	$ 149
Liability derivatives - fair value		(114)	(76)
Not designated as hedging instrument | Futures contracts
Derivative [Line Items]
Asset derivatives - fair value	[1]	129	51
Liability derivatives - fair value	[1]	(62)	(17)
Net derivatives - notional value	[2]	4,515	3,138
Not designated as hedging instrument | Foreign currency forward contracts
Derivative [Line Items]
Asset derivatives - fair value	[1]	32	39
Liability derivatives - fair value	[1]	(35)	(35)
Net derivatives - notional value	[2]	1,481	1,136
Not designated as hedging instrument | Other
Derivative [Line Items]
Asset derivatives - fair value	[1],[3]	31	59
Liability derivatives - fair value	[1],[3]	(17)	(24)
Net derivatives - notional value	[2],[3]	$ 275	$ 3,592

[1] The fair value of asset derivatives are included in ‘other assets’ and the fair value of liability derivatives are included in ‘other liabilities.’

[2] Represents the absolute notional value of all outstanding contracts, consisting of long and short positions.

[3] Includes swaps, options and other derivatives contracts.