Bank segment (HEI only) - Credit Risk Profile Based on Aging Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Credit risk profile based on nonaccrual loans
Nonaccrual loans	$ 29,736	$ 27,295
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	26,413	25,917
Residential 1-4 family
Credit risk profile based on nonaccrual loans
Nonaccrual loans	11,395	12,037
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	9,869	10,194
Commercial real estate
Credit risk profile based on nonaccrual loans
Nonaccrual loans	195	0
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	853	915
Home equity line of credit
Credit risk profile based on nonaccrual loans
Nonaccrual loans	6,638	6,348
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	10,376	11,597
Residential land
Credit risk profile based on nonaccrual loans
Nonaccrual loans	448	436
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	2,644	1,622
Commercial construction
Credit risk profile based on nonaccrual loans
Nonaccrual loans	0	0
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	0	0
Residential construction
Credit risk profile based on nonaccrual loans
Nonaccrual loans	0	0
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	0	0
Commercial
Credit risk profile based on nonaccrual loans
Nonaccrual loans	5,947	4,278
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	2,614	1,527
Consumer
Credit risk profile based on nonaccrual loans
Nonaccrual loans	5,113	4,196
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	$ 57	$ 62

Amount, after troubled debt restructuring, of modified financing receivable.

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