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Borrowings - Narrative (Details) - USD ($)				12 Months Ended
Borrowings - Narrative (Details) - USD ($)	Jul. 02, 2024	Aug. 05, 2019	Aug. 01, 2019	Dec. 31, 2019	Jul. 02, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Short-term borrowings				$ 2,669,145,000		$ 0
Debt assumed in merger			$ 442,323,000
Loans pledged as collateral				10,500,000,000
FHLB advances, amount prepayable				$ 1,500,000,000
Current Fiscal Year End Date				--12-31
Federal Home Loan Bank Advances, Maturity 2020
Debt Instrument [Line Items]
FHLB interest rate				1.30%
Federal Home Loan Bank Advances, Maturity 2025
Debt Instrument [Line Items]
FHLB interest rate				2.72%
Subordinated bank notes
Debt Instrument [Line Items]
Debt assumed in merger			19,000,000.0
Subordinated bank notes \| Subordinated Bank Notes Due 2032
Debt Instrument [Line Items]
Debt assumed in merger			5,600,000
Subordinated bank notes \| Subordinated Bank Notes Due 2034 and 2035
Debt Instrument [Line Items]
Debt assumed in merger			$ 13,400,000
Subordinated bank notes \| 2029 Notes
Debt Instrument [Line Items]
Issuance amount					$ 150,000,000.0
Stated Rate					4.125%
Issuance costs				$ 1,500,000
Revolving Line-of-Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 50,000,000.0
Debt term		364 days
Short-term borrowings				$ 0
Eurocurrency Rate \| Revolving Line-of-Credit
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.50%
Three-Month LIBOR \| Subordinated bank notes \| Subordinated Bank Notes Due 2032
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			3.25%
Three-Month LIBOR \| Subordinated bank notes \| Subordinated Bank Notes Due 2034
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			1.45%
Three-Month LIBOR \| Subordinated bank notes \| Subordinated Bank Notes Due 2035
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			2.85%
Three-Month LIBOR \| Scenario, Forecast \| Subordinated bank notes \| 2029 Notes
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.375%