Short-Term Borrowings and Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Short-Term Debt [Line Items]
Total FHLB advances	$ 3,500,000	$ 0
Weighted-average contractual interest rates for FHLB advances	4.88%
Floating
Short-Term Debt [Line Items]
Total FHLB advances	$ 3,000,000	0
Fixed
Short-Term Debt [Line Items]
Total FHLB advances	$ 500,000	0
Minimum | Floating
Short-Term Debt [Line Items]
Interest Rates	5.02%
Minimum | Fixed
Short-Term Debt [Line Items]
Interest Rates	3.87%
Maximum | Floating
Short-Term Debt [Line Items]
Interest Rates	5.07%
Maximum | Fixed
Short-Term Debt [Line Items]
Interest Rates	3.95%
Bank Term Funding Program
Short-Term Debt [Line Items]
Interest rate short-term borrowings	4.37%
Short-term borrowings	$ 0	$ 4,500,000
Parent Company | Junior Subordinated Debt
Short-Term Debt [Line Items]
Weighted-average rate (as a percent)	6.76%	6.87%
Long-term debt total	$ 31,923	$ 148,249