Name:	fhb_CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
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Common Equity Tier 1 capital divided by risk weighted assets as defined by regulations.

No definition available.

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Represents the limit of the allowable amount of the reserve for credit losses that can be added to Tier 1 capital, as a percentage of risk weighted assets, to calculate the total risk-based capital ratio as defined in the regulations.

No definition available.

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Amount of total capital as defined by regulatory framework.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Period Type:	instant

No definition available.

Name:	us-gaap_CapitalAbstract
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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework.

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Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework.

Name:	us-gaap_CommonEquityTierOneCapital
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Data Type:	xbrli:monetaryItemType
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No definition available.

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Ratio of Common Equity Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

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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.

Name:	us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems
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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

No definition available.

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Data Type:	xbrli:stringItemType
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Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
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Period Type:	instant

Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
Namespace Prefix:	us-gaap_
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Ratio of Tier 1 capital to average assets as defined by regulatory framework.

Name:	us-gaap_TierOneLeverageCapitalToAverageAssets
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Amount of Tier 1 risk-based capital as defined by regulatory framework.

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Data Type:	xbrli:monetaryItemType
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No definition available.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

Name:	us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
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Ratio of Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.