Derivative Financial Instruments - Additional Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) Contract	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) Contract
Designated as Hedging Instrument [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total excluded components of earnings recognition	$ 85,000	$ 9,000
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	1,225,000,000		$ 1,125,000,000
Interest and fees on LHFS and LHFI reclassified as a reduction over twelve months	15,500,000
Designated as Hedging Instrument [Member] | Interest Rate Floor [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	$ 1,225,000,000		$ 1,125,000,000
Derivatives not Designated as Hedging Instruments [Member] | Beneficiary [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements | Contract	7		6
Aggregate notional amount of credit risk participation agreements	$ 44,900,000		$ 40,100,000
Derivatives not Designated as Hedging Instruments [Member] | Guarantor [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements | Contract	35		35
Aggregate notional amount of credit risk participation agreements	$ 304,100,000		$ 304,700,000
Derivatives not Designated as Hedging Instruments [Member] | Mortgage Servicing Rights Hedge [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	301,000,000		285,000,000
Net (negative) positive ineffectiveness on MSR fair value	(1,100,000)	$ (1,800,000)
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	1,470,000,000		1,500,000,000
Termination value of derivatives	0		1,400,000
Collateral Posted	40,000		2,000,000
Derivatives not Designated as Hedging Instruments [Member] | Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	128,500,000		109,500,000
Valuation adjustment	(208,000,000)		(994,000)
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Lock Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	88,500,000		61,900,000
Valuation adjustment	$ 1,200,000		$ 845,000