Allowance for Loan Losses - Schedule of Loan Modifications Related to Covid-19 (Details) $ in Thousands	Dec. 31, 2021 USD ($) contract	Dec. 31, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| contract	24	237
Outstanding Recorded Investment \| $	$ 1,371	$ 20,003
Real Estate- Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| contract	1	11
Outstanding Recorded Investment \| $	$ 258	$ 7,106
Real Estate- Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| contract	0	4
Outstanding Recorded Investment \| $	$ 0	$ 1,849
Real Estate - Construction and Land
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| contract	0	2
Outstanding Recorded Investment \| $	$ 0	$ 1,424
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| contract	23	220
Outstanding Recorded Investment \| $	$ 1,113	$ 9,624

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.

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

+ Details

Name:	us-gaap_FinancingReceivableModificationsRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=fhbi_ResidentialRealEstateSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=fhbi_ConstructionAndLandRealEstateSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=fhbi_CommercialAndIndustrialSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: