Leases - Future Minimum Rental Payments under Noncancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Future minimum rental payments under noncancelable operating leases
2021	$ 8,928
2022	6,334
2023	3,833
2024	3,601
2025	2,937
Thereafter	42,746
Total future minimum lease payments	68,379
Less: Imputed interest	(20,792)
Total	$ 47,587

Amount of interest expense on operating lease liability.

No definition available.

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- Definition

Amount, before imputed interest, of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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Namespace Prefix:	fhb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

+ Details

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