Disclosures About Fair Value of Financial Instruments - Nonrecurring Assets that had Fair Market Values Below the Carrying Amount (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Level 1
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	$ 0	$ 0
Total assets	277,172	169,613
Level 2
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Total assets	1,740,382	1,784,996
Level 3
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	10,270,432	10,274,593
Total assets	10,279,987	10,284,002
Nonrecurring
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Mortgage servicing rights	19	133
Real estate owned, net	74	104
Total assets	41,932	36,984
Nonrecurring \| Loans individually assessed
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	41,839	36,747
Nonrecurring \| Level 1
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Mortgage servicing rights	0	0
Real estate owned, net	0	0
Total assets	0	0
Nonrecurring \| Level 1 \| Loans individually assessed
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Nonrecurring \| Level 2
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Mortgage servicing rights	0	0
Real estate owned, net	0	0
Total assets	0	0
Nonrecurring \| Level 2 \| Loans individually assessed
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Nonrecurring \| Level 3
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Mortgage servicing rights	19	133
Real estate owned, net	74	104
Total assets	41,932	36,984
Nonrecurring \| Level 3 \| Loans individually assessed
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	$ 41,839	$ 36,747

Mortgage Servicing Rights, Fair Value

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- Definition

Fair value portion of asset recognized for present right to economic benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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+ References

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- Definition

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://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

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- Definition

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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