Derivative Instruments - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Net unrealized gains (losses) arising during the period	$ (40,606,000)	$ (298,289,000)	$ (77,948,000)
Unrealized gain, after tax	(30,791,000)	(225,715,000)	(57,705,000)
Pre-tax income	(23,700,000)	3,800,000	12,900,000
Cash flow hedge loss to be reclassified	117,000,000
Cash flow hedge termination loss	21,000,000
Reclaim cash collateral	69,700,000	66,800,000
Obligation to return cash collateral	$ 5,700,000	7,700,000
Mortgage derivatives
Derivative [Line Items]
Derivative, term of contract	90 days
Cash Flow Hedging
Derivative [Line Items]
Net unrealized gains (losses) arising during the period	$ 0	(57,400,000)	1,200,000
Unrealized gain, after tax	0	$ (43,400,000)	$ 930,000
Fair Value Hedging | Interest rate contracts | Interest-bearing deposits
Derivative [Line Items]
Hedged liability, discontinued fair value hedge	150,000,000
Fair Value Hedging | Interest rate contracts | Long-Term Debt
Derivative [Line Items]
Hedged liability, discontinued fair value hedge	$ 496,700,000