Represents the percentage of a loan sold with no recourse to not be subject to grading for credit quality.

No definition available.

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Namespace Prefix:	fhb_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Represents the number of risk factors in internal rating system for credit quality of financing receivables.

+ References

No definition available.

+ Details

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Namespace Prefix:	fhb_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- 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

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_NonperformingFinancingReceivableMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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Allowance for Loan and Lease Losses - Credit Risk Profiles Based on Payment Activity, Not Subject to Loan Grading (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) factor	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Loans and Leases Receivable Disclosure [Line Items]
Percentage of loans sold with no recourse not subject to grading	100.00%
Number of risk factors in internal loan rating system \| factor	8
Loans and leases	$ 13,211,650	$ 13,076,191	$ 12,277,369
Residential and consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	6,282,731	6,102,122
Residential and consumer \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	6,229,130	6,040,469
Residential and consumer \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	53,601	61,653
Residential
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	4,662,175	4,439,618	4,090,053
Residential \| Residential mortgage
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	3,768,936	3,527,101
Residential \| Residential mortgage \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	3,759,799	3,519,172
Residential \| Residential mortgage \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	9,137	7,929
Home equity Line \| Home equity
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	893,239	912,517
Home equity Line \| Home equity \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	886,879	903,284
Home equity Line \| Home equity \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	6,360	9,233
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	1,620,556	1,662,504	$ 1,586,476
Consumer \| Consumer loans
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	226,304	239,906
Consumer \| Consumer loans \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	219,046	234,458
Consumer \| Consumer loans \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	7,258	5,448
Consumer \| Consumer - Auto
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	1,040,468	1,078,132
Consumer \| Consumer - Auto \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	1,016,142	1,044,393
Consumer \| Consumer - Auto \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	24,326	33,739
Consumer \| Credit Cards
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	353,784	344,466
Consumer \| Credit Cards \| Performing
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	347,264	339,162
Consumer \| Credit Cards \| Non-performing and delinquent
Loans and Leases Receivable Disclosure [Line Items]
Loans and leases	$ 6,520	$ 5,304