Summary of Significant Accounting Policies - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investment Securities - Held to Maturity	$ 2,195,980	$ 2,254,670
Net book balance	1,000
Accrued interest receivable (AIR)	$ 182,500	$ 133,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets.	Other Assets.
Liability recorded for expected credit losses on unfunded commitments	$ 62,300
Other Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accrued interest receivable for investment securities	36,700	$ 24,200
Other Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liability recorded for expected credit losses on unfunded commitments	$ 62,300	$ 45,300