Derivatives and Hedging Activities - Schedule of Master Netting Arrangements (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Derivative Asset [Abstract]
Derivative Asset, Fair Value, Gross Asset	$ 26.6	$ 44.9
Derivative Asset, Fair Value, Gross Liability	0.0	0.0
Derivative, Collateral, Obligation to Return Securities	0.0	0.0
Derivative, Collateral, Obligation to Return Cash	26.4	42.4
Derivative Asset, Fair Value, Amount Offset Against Collateral, Total	0.2	2.5
Offsetting Derivative Liabilities [Abstract]
Derivative Liability, Fair Value, Gross Liability	77.3	133.8
Derivative Liability, Fair Value, Gross Asset	0.0	0.0
Derivative, Collateral, Right to Reclaim Securities	0.0	0.0
Derivative, Collateral, Right to Reclaim Cash	0.0	0.0
Derivative Liability, Fair Value, Amount Offset Against Collateral, Total	77.3	133.8
Securities Sold under Agreements to Repurchase, Amount Offset Against Collateral [Abstract]
Securities Sold under Agreements to Repurchase, Gross	479.6	523.9
Securities Sold under Agreements to Repurchase, Asset	0.0	0.0
Securities Sold under Agreements to Repurchase, Total	479.6	523.9
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities	0.0	0.0
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Cash	0.0	0.0
Securities Sold under Agreements to Repurchase, Amount Offset Against Collateral, Total	479.6	523.9
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Gross	556.9	657.7
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Asset	0.0	0.0
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Total	556.9	657.7
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Collateral, Right to Reclaim Securities	0.0	0.0
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Collateral, Right to Reclaim Cash	0.0	0.0
Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Amount Offset Against Collateral, Total	556.9	657.7
Derivative Asset, Notional Amount	1,201.0	1,420.5
Derivative Assets, Estimated Fair Value	26.6	44.9
Derivative Liability, Notional Amount	1,269.5	2,107.0
Net Liabilities in the Balance Sheet	77.3	133.8
Interest Rate Swap [Member]
Derivative Asset [Abstract]
Derivative Asset, Fair Value, Gross Asset	26.6	44.9
Derivative Asset, Fair Value, Gross Liability	0.0	0.0
Derivative, Collateral, Obligation to Return Securities	0.0	0.0
Derivative, Collateral, Obligation to Return Cash	26.4	42.4
Derivative Asset, Fair Value, Amount Offset Against Collateral, Total	0.2	2.5
Offsetting Derivative Liabilities [Abstract]
Derivative Liability, Fair Value, Gross Liability	77.3
Derivative Liability, Fair Value, Gross Asset	0.0
Derivative, Collateral, Right to Reclaim Securities	0.0
Derivative, Collateral, Right to Reclaim Cash	0.0
Derivative Liability, Fair Value, Amount Offset Against Collateral, Total	77.3
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Assets, Estimated Fair Value	26.6	44.9
Net Liabilities in the Balance Sheet	77.3
Interest Rate Swap [Member] | Not Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Asset, Notional Amount	1,199.0	1,415.4
Derivative Assets, Estimated Fair Value	26.6	44.9
Derivative Liability, Notional Amount	1,204.9	1,415.4
Net Liabilities in the Balance Sheet	77.3	130.0
Interest Rate Swap [Member] | Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Liability, Notional Amount	0.0	300.0
Net Liabilities in the Balance Sheet	0.0	2.8
Forward Contracts [Member] | Not Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Asset, Notional Amount	1.0	2.4
Derivative, Fair Value, Net	0.0	0.0
Interest Rate Collars | Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Liability, Notional Amount	0.0	300.0
Net Liabilities in the Balance Sheet	0.0	1.0
Risk Participation Agreements | Not Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Liability, Notional Amount	64.6	91.6
Net Liabilities in the Balance Sheet	0.0	0.0
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Derivative Asset, Notional Amount	1.0	2.7
Derivative Assets, Estimated Fair Value	$ 0.0	0.0
Interest Rate Swap and Interest Rate Collar
Offsetting Derivative Liabilities [Abstract]
Derivative Liability, Fair Value, Gross Liability		133.8
Derivative Liability, Fair Value, Gross Asset		0.0
Derivative, Collateral, Right to Reclaim Securities		0.0
Derivative, Collateral, Right to Reclaim Cash		0.0
Derivative Liability, Fair Value, Amount Offset Against Collateral, Total		133.8
Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract]
Net Liabilities in the Balance Sheet		$ 133.8