Derivative Instruments - Fair value and notional amount of derivatives (Details) - USD ($) $ in Millions		Jun. 30, 2024	Dec. 31, 2023
Derivative offsetting
Derivative assets subject to master netting agreements		$ 116	$ 197
Derivative liabilities subject to master netting agreements		$ 60	$ 119
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		$ 116	$ 197
Liability derivatives - fair value		(60)	(119)
Not designated as hedging instrument | Futures contracts
Derivative [Line Items]
Asset derivatives - fair value	[1]	68	139
Liability derivatives - fair value	[1]	(11)	(61)
Net derivatives - notional value	[2]	3,395	3,746
Not designated as hedging instrument | Foreign currency forward contracts
Derivative [Line Items]
Asset derivatives - fair value	[1]	8	27
Liability derivatives - fair value	[1]	(12)	(32)
Net derivatives - notional value	[2]	1,281	1,224
Not designated as hedging instrument | Other
Derivative [Line Items]
Asset derivatives - fair value	[1],[3]	40	31
Liability derivatives - fair value	[1],[3]	(37)	(26)
Net derivatives - notional value	[2],[3]	$ 420	$ 512

[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.