Allowance for accrued interest receivable.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Available commitments under revolving credit lines that have been modified as TDRs.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass.

+ References

No definition available.

+ Details

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- Definition

Represents the number of days past due following modification of loans in a troubled debt restructuring, when a loan is considered to be in default.

+ References

No definition available.

+ Details

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- Definition

Financing receivable modified residential mortgage and or home equity loans maximum term categorized as classified credit quality indicator if principal and interest are current.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Financing receivable past due for loans and leases to be classified as classified credit quality indicator period.

+ References

No definition available.

+ Details

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- Definition

Financing receivable recorded investment nonaccrual status current not past due period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Loan and lease modifications amount.

+ References

No definition available.

+ Details

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

- Definition

Number of Loan and Lease Concessions

+ References

No definition available.

+ Details

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Namespace Prefix:	boh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Revolving Loans, Converted To Term Loan During the Period

+ References

No definition available.

+ Details

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Namespace Prefix:	boh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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-Paragraph 1B
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Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-SubTopic 10
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

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Loans and Leases and the Allowance for Credit Losses - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Loan
Loan and lease portfolio
Net gains related to sales of residential mortgage loans	$ 1,200	$ 3,400	$ 5,900	$ 9,000
Accrued interest receivable	46,751		46,751		$ 49,303
Revolving loans, converted to term loan during the period			$ 2,500	$ 1,300
Number of days non-accrual loans are not past due			30 days
Recorded Investment	72,700		$ 72,700		72,500
Available commitments to lend additional funds on loans modified as TDR			200		500
AIR allowance	700		700		$ 2,700
Consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure	$ 1,500		$ 1,500
Consumer
Loan and lease portfolio
Number of loan and lease concessions - COVID-19 \| Loan	31		31		1,920
Loan and lease modifications, amount - COVID-19	$ 7,500		$ 7,500		$ 178,100
Commercial
Loan and lease portfolio
Number of loan and lease concessions - COVID-19 \| Loan	23		23		210
Loan and lease modifications, amount - COVID-19	$ 130,400		$ 130,400		$ 311,600
Pass \| Residential Mortgage
Loan and lease portfolio
Number of days past due for loans and leases in classified credit quality indicator			90 days
Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)			60.00%
Pass \| Home Equity
Loan and lease portfolio
Number of days past due for loans and leases in classified credit quality indicator			90 days
Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)			60.00%
Classified
Loan and lease portfolio
Number of months up to which residential and home equity loans may be considered classified, even if they are current as to principal and interest			6 months
Classified \| Consumer
Loan and lease portfolio
Number of days past due for loans and leases in classified credit quality indicator			90 days
Minimum
Loan and lease portfolio
Default period past due following modification of loans in TDR (in days)			60 days
PPP Loans, Administered by the SBA
Loan and lease portfolio
Loans interest rate	1.00%		1.00%
PPP Loans, Administered by the SBA \| Minimum
Loan and lease portfolio
Loans maturity period			2 years
PPP Loans, Administered by the SBA \| Maximum
Loan and lease portfolio
Loans maturity period			5 years
Accrued Interest Receivable
Loan and lease portfolio
Accrued interest receivable	$ 29,900		$ 29,900		$ 35,900