Represents the interest receivable written off by reversing interest income.

No definition available.

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Period Type:	duration

- Definition

The amount of interest income on impaired and nonperforming loans that is due to the change in present value attributable to the passage of time.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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Balance Type:	debit
Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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

- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (3)
-Publisher SEC

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (2)
-Publisher SEC

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
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Data Type:	na
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- Details

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Namespace Prefix:
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Period Type:

- Details

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Period Type:

- Details

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Allowance for Credit Losses - Nonaccrual Loans and Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases With No Allowance for Credit Losses	$ 5,617		$ 4,996
Nonaccrual Loans and Leases	20,188		20,679
Interest income recognized on nonaccrual loans and leases	400	$ 200
Accrued interest receivables written off, Interest income reversed	300	$ 200
Commercial and Industrial
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases			329
Commercial Real Estate
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases	216		411
Construction
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases	375
Residential mortgage
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases With No Allowance for Credit Losses	5,617		4,495
Nonaccrual Loans and Leases	12,809		12,768
Home equity Line
Financing Receivable, Nonaccrual
Nonaccrual Loans and Leases With No Allowance for Credit Losses			501
Nonaccrual Loans and Leases	$ 6,788		$ 7,171