Fair Value Measurements - Assets Measured at Fair Value (Detail) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Fair Value	$ 26,747	$ 52,276
Valuation Technique	Discounted cash flow	Discounted cash flow
Unobservable Input	Discount rate	Discount rate
Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Fair Value	$ 251	$ 3,178
Valuation Technique	Appraisal of collateral	Appraisal of collateral
Unobservable Input	Appraisal adjustments	Appraisal adjustments
Minimum [Member] \| Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	0.00%
Securities AFS, Unobservable Input Value or Range		0
Minimum [Member] \| Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	0.00%
Impaired Loans, Unobservable Input Value or Range		0
Maximum [Member] \| Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	1.00%
Securities AFS, Unobservable Input Value or Range		1.0
Maximum [Member] \| Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	22.00%
Impaired Loans, Unobservable Input Value or Range		17

Fair value investment classified at unobservable input.

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- Definition

Fair value investment classified at unobservable input range.

+ References

No definition available.

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- Definition

Fair Value Measurements Valuation Technique

+ 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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Balance Type:	debit
Period Type:	instant

- Definition

Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

+ 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

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- Definition

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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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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