Derivatives and Hedging Activities - Schedule of Notional Amounts of Outstanding Derivative Positions (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Derivative Assets (included in other assets on the consolidated balance sheets):
Derivative Asset, Notional Amount	$ 1,646.8	$ 2,290.7
Derivative Asset, Estimated Fair Value	57.4	45.2
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets):
Derivative Liabilities, Notional Amount	2,898.0	2,449.0
Derivative Liabilities, Estimated Fair Value	210.0	159.6
Not Designated as Hedging Instrument | Interest rate swap contracts
Derivative Assets (included in other assets on the consolidated balance sheets):
Derivative Asset, Notional Amount	1,638.8	1,728.1
Derivative Asset, Estimated Fair Value	57.4	41.6
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets):
Derivative Liabilities, Notional Amount	1,638.8	1,728.1
Derivative Liabilities, Estimated Fair Value	184.1	153.9
Not Designated as Hedging Instrument | Interest rate lock commitments
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets):
Derivative Liabilities, Notional Amount	7.0	14.8
Derivative Liabilities, Estimated Fair Value	0.0	0.0
Not Designated as Hedging Instrument | Forward loan sales contracts
Derivative Assets (included in other assets on the consolidated balance sheets):
Derivative Asset, Notional Amount	8.0	12.6
Designated as Hedging Instrument [Member] | Interest rate swap contracts
Derivative Assets (included in other assets on the consolidated balance sheets):
Derivative Asset, Notional Amount	0.0	550.0
Derivative Asset, Estimated Fair Value	0.0	3.5
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets):
Derivative Liabilities, Notional Amount	850.0	300.0
Derivative Liabilities, Estimated Fair Value	$ 18.6	$ 0.3