Bank segment (HEI only) - Credit Risk Profile Based on Aging Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Credit risk profile based on nonaccrual loans
Nonaccrual loans	$ 27,295	$ 23,591
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	25,917	20,814
Residential 1-4 family
Credit risk profile based on nonaccrual loans
Nonaccrual loans	12,037	12,598
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	10,194	10,982
Commercial real estate
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	915	1,016
Home equity line of credit
Credit risk profile based on nonaccrual loans
Nonaccrual loans	6,348	4,466
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	11,597	6,584
Residential land
Credit risk profile based on nonaccrual loans
Nonaccrual loans	436	841
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	1,622	425
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	4,278	3,069
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	1,527	1,741
Consumer
Credit risk profile based on nonaccrual loans
Nonaccrual loans	4,196	2,617
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	$ 62	$ 66

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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No definition available.

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