Bank segment (HEI only) - Credit Risk Profile Based on Aging Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Credit risk profile based on nonaccrual loans
Nonaccrual loans	$ 23,591	$ 23,325
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	20,814	37,637
Residential 1-4 family
Credit risk profile based on nonaccrual loans
Nonaccrual loans	12,598	11,154
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	10,982	14,450
Commercial real estate
Credit risk profile based on nonaccrual loans
Nonaccrual loans	0	223
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	1,016	1,346
Home equity line of credit
Credit risk profile based on nonaccrual loans
Nonaccrual loans	4,466	3,080
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	6,584	4,934
Residential land
Credit risk profile based on nonaccrual loans
Nonaccrual loans	841	878
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	425	2,751
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	3,069	6,708
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	1,741	14,146
Consumer
Credit risk profile based on nonaccrual loans
Nonaccrual loans	2,617	1,282
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	$ 66	$ 10

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

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+ References

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No definition available.

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