Consumer Credit Exposures Period Past Due Required To Classify Loans As Special Mention Maximum.

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Maximum exposure to credit risk of loans or receivables.

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Financing Receivable, Collateral Dependent Loans

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No definition available.

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Financing Receivable, Modified, Number Of Additional Commitments To Lend

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Mortgage Loans In Process Of Foreclosure, Number

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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No definition available.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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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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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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The aggregate amount of the participating mortgage obligation at the end of the accounting period.

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Loans and Allowance for Credit Losses - Additional Information (Details)	3 Months Ended
	Mar. 31, 2025 USD ($) loan	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) commitment loan	Dec. 31, 2023 USD ($)
Changes in lines of credit,resrticted to commercial exposure
Loan syndications, amount	$ 100,000,000
Financing receivable, excluding accrued interest, after allowance for credit loss	17,691,385,000		$ 17,549,402,000
Debt, long-term and short-term, combined amount	54,909,000		66,179,000
Mortgage loans partially or wholly-owned by others and serviced by the Company	222,300,000		228,400,000
Allowance for loan losses decreased	$ 4,600,000
Percentage of allowance for loan losses decrease (as a percent)	2.00%
Financing receivable, allowance for credit loss, excluding accrued interest	$ 224,310,000	$ 149,190,000	228,952,000	$ 148,993,000
Maximum number of days required for special mention	90 days
Loans modified during the prior 12 months which had subsequently defaulted	$ 0	0
Financing receivable, modified, commitment to lend	0		$ 300,000
Number of additional commitments to lend \| commitment			1
Federal Home Loan Bank Advances \| Asset Pledged as Collateral
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, excluding accrued interest, after allowance for credit loss	2,200,000,000		$ 2,300,000,000
Federal Reserve Bank Advances \| Asset Pledged as Collateral
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, excluding accrued interest, after allowance for credit loss	3,600,000,000		3,100,000,000
Commercial Portfolio Segment
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, collateral dependent loans	63,000,000.0		107,700,000
Residential Real Estate
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, collateral dependent loans	1,600,000		1,100,000
Unfunded Loan Commitment
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, allowance for credit loss, excluding accrued interest	13,000,000.0		13,100,000
Residential real estate \| Residential Real Estate
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, allowance for credit loss, excluding accrued interest	$ 31,096,000	25,935,000	$ 32,291,000	25,954,000
Number of loans in process of foreclosure \| loan	7		4
Mortgage loans in process of foreclosure, amount	$ 800,000		$ 400,000
Consumer home equity \| Consumer Portfolio Segment
Changes in lines of credit,resrticted to commercial exposure
Financing receivable, allowance for credit loss, excluding accrued interest	$ 6,891,000	$ 5,684,000	$ 7,472,000	$ 5,595,000
Number of loans in process of foreclosure \| loan	5		6
Mortgage loans in process of foreclosure, amount	$ 600,000		$ 500,000
Federal Home Loan Bank Advances
Changes in lines of credit,resrticted to commercial exposure
Advance from Federal Home Loan Bank	20,100,000		17,600,000
Federal Reserve Bank Advances
Changes in lines of credit,resrticted to commercial exposure
Debt, long-term and short-term, combined amount	0		$ 0
Unrated \| Minimum
Changes in lines of credit,resrticted to commercial exposure
Lines of credit, exposure	100,000
Unrated \| Line of Credit \| Commercial Portfolio Segment \| Maximum
Changes in lines of credit,resrticted to commercial exposure
Lines of credit, exposure	1,500,000
Unrated \| Line of Credit \| Business Banking \| Commercial Portfolio Segment \| Maximum
Changes in lines of credit,resrticted to commercial exposure
Lines of credit, exposure	$ 1,500,000