Derivatives and Hedging - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) item contract	Dec. 31, 2022 item	Dec. 31, 2023 USD ($) item contract
Derivatives and Hedging
Collateral paid	$ 1.1		$ 1.0
Collateral received	$ 0.6		$ 1.5
Interest Rate Swap | Designated as Hedging Instrument
Derivatives and Hedging
Number of cash flow hedges matured | item	2
Number of cash flow hedges terminated | item	2
Number of instruments | item	1		5
Notional Amount	$ 250.0		$ 340.0
Derivative instruments to be reclassified to interest income in next 12 months	$ 3.3
Number of hedges terminated | item	2	5
Maximum exposure period	2 years 9 months 18 days
Interest Rate Swap | Not Designated as Hedging Instrument
Derivatives and Hedging
Number of instruments | contract	46		46
Notional Amount	$ 323.0		$ 307.0