Bank segment (HEI only) - Credit Risk Profile Based on Aging Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Credit risk profile based on nonaccrual loans
Nonaccrual loans	$ 23,325	$ 46,035
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	37,637	22,246
Residential 1-4 family
Credit risk profile based on nonaccrual loans
Nonaccrual loans	11,154	20,554
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	14,450	13,962
Commercial real estate
Credit risk profile based on nonaccrual loans
Nonaccrual loans	223	1,188
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	1,346	0
Home equity line of credit
Credit risk profile based on nonaccrual loans
Nonaccrual loans	3,080	2,254
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	4,934	2,467
Residential land
Credit risk profile based on nonaccrual loans
Nonaccrual loans	878	970
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	2,751	4,713
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 loans
Credit risk profile based on nonaccrual loans
Nonaccrual loans	6,708	20,174
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	14,146	1,104
Consumer loans
Credit risk profile based on nonaccrual loans
Nonaccrual loans	1,282	895
Accruing loans 90 days or more past due	0	0
Troubled debt restructured loans not included above	$ 10	$ 0

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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+ 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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