Fair Value Measurements - Qualitative Valuation (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Measured on non-recurring basis
Fair Value
Impaired loans	$ 4,860	$ 5,000
Mortgage servicing rights	2,756	2,908
Significant Unobservable Inputs (Level 3)
Fair Value
Impaired loans	7,229,292	7,366,184
Significant Unobservable Inputs (Level 3) \| Measured on non-recurring basis
Fair Value
Impaired loans	4,860	5,000
Mortgage servicing rights	$ 2,756	$ 2,908
Significant Unobservable Inputs (Level 3) \| Contracted modification agreement \| Measured on non-recurring basis \| Other
Unobservable Inputs
Impaired loans	0	0
Significant Unobservable Inputs (Level 3) \| Contracted modification agreement \| Measured on non-recurring basis \| Weighted Average \| Other
Unobservable Inputs
Impaired loans	0	0
Significant Unobservable Inputs (Level 3) \| Prepayment speeds and discount rates \| Measured on non-recurring basis \| Minimum \| Discounted cash flow
Unobservable Inputs
Mortgage servicing rights	0.049	0.043
Significant Unobservable Inputs (Level 3) \| Prepayment speeds and discount rates \| Measured on non-recurring basis \| Maximum \| Discounted cash flow
Unobservable Inputs
Mortgage servicing rights	0.270	0.272
Significant Unobservable Inputs (Level 3) \| Prepayment speeds and discount rates \| Measured on non-recurring basis \| Weighted Average \| Discounted cash flow
Unobservable Inputs
Mortgage servicing rights	0.089	0.081
Significant Unobservable Inputs (Level 3) \| Discount rate \| Measured on non-recurring basis \| Weighted Average \| Discounted cash flow
Unobservable Inputs
Mortgage servicing rights	0.1550

Fair Value Measurement Inputs And Valuation Techniques, Fair Value

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Fair Value Measurement Inputs And Valuation Techniques, Unobservable Inputs

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Impaired Financing Receivable, Measurement Input

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Publisher FASB
-URI https://asc.fasb.org//310-10/tableOfContent

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

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-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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-Name Accounting Standards Codification
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Value of input used to measure servicing asset.

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-Topic 820
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