Employee Stock Ownership Plan - Employee Stock Ownership Plan (ESOP) Disclosures (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Mar. 31, 2019
Shares committed to be released	5,265	7,021
Total allocated shares	7,021	0
Total unallocated shares	163,242	168,507	175,528
Total ESOP shares	175,528	175,528
Fair value of unallocated shares (based on $9.26 and $10.78 share price as of September 30, 2020 and December 31, 2019, respectively)	$ 1,512	$ 1,817

Represents number of shares for which compensation cost not allocated.

No definition available.

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Data Type:	xbrli:sharesItemType
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- Definition

Shares committed to be released.

+ References

No definition available.

+ Details

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- Definition

Fair value of unearned shares held by the employee stock ownership plan (ESOP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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Period Type:	instant

- Definition

The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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- Definition

Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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