Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis by Significant Unobservable Inputs (Details) - Fair Value, Measurements, Nonrecurring	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities measured at fair value on a nonrecurring basis	$ 0	$ 0
Level 3
ASSETS
Total Assets	89,137,000	74,917,000
Collateral method \| Level 3
ASSETS
Loans individually evaluated	78,186,000	67,402,000
Other real estate owned	1,563,000	1,953,000
Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights	6,590,000	4,976,000
Contractual agreement \| Level 3
ASSETS
Loans held for sale	$ 2,798,000	$ 586,000
Minimum \| Appraisal adjustment \| Collateral method \| Level 3
ASSETS
Loans held for investment, measurement input	0	0
Minimum \| Costs to sell \| Collateral method \| Level 3
ASSETS
Other real estate owned, measurement input	0.04	0.04
Minimum \| Discount rate \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.0902	0.0924
Minimum \| Constant prepayment rates \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.0924	0.0882
Maximum \| Appraisal adjustment \| Collateral method \| Level 3
ASSETS
Loans held for investment, measurement input	0.47	0.47
Maximum \| Costs to sell \| Collateral method \| Level 3
ASSETS
Other real estate owned, measurement input	0.0700	0.0700
Maximum \| Discount rate \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.1377	0.1255
Maximum \| Constant prepayment rates \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.1254	0.1458
Weighted Average \| Appraisal adjustment \| Collateral method \| Level 3
ASSETS
Loans held for investment, measurement input	0.1691	0.1690
Weighted Average \| Costs to sell \| Collateral method \| Level 3
ASSETS
Other real estate owned, measurement input	0.0506	0.0492
Weighted Average \| Discount rate \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.0940	0.0942
Weighted Average \| Constant prepayment rates \| Discounted cash flow method \| Level 3
ASSETS
Mortgage servicing rights, measurement input	0.1108	0.1337

Loans Receivable, Measurement Input

No definition available.

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- Definition

Other real estate owned fair value disclosure.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

+ References

No definition available.

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- References

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

+ Details

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

+ Details

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- Definition

Value of input used to measure servicing asset.

+ References

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