Allowance for Loan Losses - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Receivables [Abstract]
Impaired loans, unsold guaranteed balance	$ 6,197	$ 6,259
Estimated amount of loan loss reserves impaired	38	$ 0
Unguaranteed portion of guaranteed loan threshold for reserved in full	$ 100

Impaired Financing Receivable, Unguaranteed Portion Of Guaranteed Loan Threshold For Reserves

No definition available.

Name:	fhbi_ImpairedFinancingReceivableUnguaranteedPortionOfGuaranteedLoanThresholdForReserves
Namespace Prefix:	fhbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant