Allowance for Credit Losses and Credit Quality of Loans, Summary (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 117,000	$ 116,000	$ 115,300	$ 114,400
Percentage of allowance for credit losses	1.17%	1.16%
Percentage of allowance for credit loss decrease	3.00%
Loans purchased with credit deterioration	$ 0	$ 0
Forecast scenario weighting, baseline	75.00%	80.00%
Forecast scenario weighting, downside	25.00%	20.00%
Accrued Interest Receivable [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 0	$ 0
AIR on loans	$ 34,800	$ 34,800
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Residential [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 26,574	$ 26,560	$ 23,409	$ 22,070
Amount of loans purchased	$ 1,300	$ 3,000
Premium on loans purchased	6.60%	7.00%
Allowance for credit losses on loans purchased	$ 13	$ 31

Percentage of decrease of allowance for credit loss during period due to model refreshment.

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- Definition

Baseline probability weighted scenario to calculate expected credit losses.

+ References

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- Definition

Downside probability weighted scenario to calculate expected credit losses.

+ References

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- Definition

Amount of loans purchased with credit deterioration during the period.

+ References

No definition available.

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- Definition

The premium percentage on loans purchased.

+ References

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- Definition

Percentage of allowance for credit loss to total financing receivable outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (1)
-Publisher SEC

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- References

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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- Definition

Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

+ References

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

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- Definition

Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

+ References

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- Definition

The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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