Derivative Instruments - Schedule of Collateral Amounts With Rights to Reclaim or Obligation to Return Cash (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Credit Derivatives [Line Items]
Collateral Posted by Counterparty	$ 9,023	$ 7,784
Collateral Posted to Counterparty	(7)	(18)
AA-
Credit Derivatives [Line Items]
Collateral Posted by Counterparty	2,407	2,867
Collateral Posted to Counterparty	(2)	(3)
A+
Credit Derivatives [Line Items]
Collateral Posted by Counterparty	5,659	4,613
Collateral Posted to Counterparty	(5)	(15)
A
Credit Derivatives [Line Items]
Collateral Posted by Counterparty	63	64
Collateral Posted to Counterparty	0	0
A-
Credit Derivatives [Line Items]
Collateral Posted by Counterparty	894	240
Collateral Posted to Counterparty	$ 0	$ 0