Employee Stock Ownership Plan - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Jan. 31, 2021	Apr. 30, 2017
Share-Based Payment Arrangement [Abstract]
Note payable balance of ESOP	$ 5,400,000		$ 5,400,000		$ 5,400,000	$ 3,000,000.0	$ 3,000,000.0
Shares purchased by ESOP						225,721	295,499
ESOP expense	$ 79,000	$ 65,000	$ 160,000	$ 122,000
ESOP released shares	59,000		59,000		59,000

Employee stock ownership plan ESOP number of released shares.

No definition available.

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Namespace Prefix:	afbi_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

The amount of plan compensation cost recognized during the period.

+ 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 (c)
-URI https://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount reported as a liability as of the balance sheet date by the entity (the employer) of the loan made by a third-party lender to the employer relating to loans made by the employer to the ESOP.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 25
-Paragraph 9
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=109244457&loc=d3e16545-113920

+ Details

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Balance Type:	credit
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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 https://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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