Loans and Leases and the Allowance for Credit Losses - Schedule of Aging Analysis by Class of Loan and Lease Portfolio (Parenthetical) (Details)	3 Months Ended
Mar. 31, 2022
Loans And Leases And Allowance For Loan And Lease Losses [Abstract]
Number of days non-accrual loans and leases are not past due	30 days

Represents the number of days that the nonaccrual loans that are not past due.

No definition available.

Name:	boh_FinancingReceivableRecordedInvestmentsNonaccrualStatusCurrentNumberOfDaysNotPastDue
Namespace Prefix:	boh_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration