Derivative Instruments - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Net unrealized gains (losses) arising during the period	$ (70,101,000)	$ (40,606,000)	$ (298,289,000)
Unrealized gain (loss), after tax	(53,173,000)	(30,791,000)	(225,715,000)
Pre-tax income (loss)	(20,600,000)	(23,700,000)	3,800,000
Cash flow hedge loss to be reclassified	54,000,000
Cash flow hedge termination loss	17,000,000
Reclaim cash collateral	34,600,000	69,700,000
Obligation to return cash collateral	$ 4,600,000	5,700,000
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	0	(57,400,000)
Unrealized gain (loss), after tax	0	0	$ (43,400,000)
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	$ 198,400,000	$ 496,700,000

Amortization Of Terminated Cash Flow Hedges, Income (Loss) Recognized

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- Definition

Cash Flow Hedge Termination Gain (Loss) To Be Reclassified Within Twelve Months

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Hedged Liability, Discontinued Fair Value Hedge

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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