Derivatives - Schedule of Notional Amounts and the Gross Fair Values of RPAs Sold and Purchased Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Derivative [Line Items]
Derivative assets - Fair value	$ 470,335	$ 409,467
Derivative liabilities - Fair value	433,751	385,973
Derivatives not Designated as Hedging Instruments
Derivative [Line Items]
Notional Amount	23,604,378	23,840,799
Derivative assets - Fair value	447,724	369,470
Derivative liabilities - Fair value	428,432	385,834
Credit contracts | Derivatives not Designated as Hedging Instruments
Derivative [Line Items]
Notional Amount	348,244	303,421
Derivative assets - Fair value	16	25
Derivative liabilities - Fair value	129	51
Credit contracts | Derivatives not Designated as Hedging Instruments | RPAs — protection sold
Derivative [Line Items]
Notional Amount	178,620	133,756
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	$ 129	$ 51
Weighted average remaining maturity of outstanding RPAs	3 years 6 months	2 years 8 months 12 days
Credit contracts | Derivatives not Designated as Hedging Instruments | RPAs — protection purchased
Derivative [Line Items]
Notional Amount	$ 169,624	$ 169,665
Derivative assets - Fair value	16	25
Derivative liabilities - Fair value	$ 0	$ 0