Bank segment (HEI only) Mortgage Servicing Rights and Valuation Allowance Roll Forward (Details) - American Savings Bank (ASB) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Mortgage Servicing Rights [Roll Forward]
Beginning balance	$ 11,540
Ending balance	8,884	$ 11,540
Allowance for mortgage-servicing assets – bank
Mortgage Servicing Rights [Roll Forward]
Beginning balance	11,749	11,938	$ 11,316
Amount capitalized	3,123	1,637	2,611
Amortization	(2,682)	(1,731)	(1,802)
Sale of mortgage servicing rights	(3,302)	0	0
Other-than-temporary impairment	(4)	(95)	(187)
Ending balance	8,884	11,749	11,938
Valuation Allowance [Roll Forward]
Valuation allowance, beginning balance	209	251	498
Provision (recovery)	(205)	53	(60)
Other-than-temporary impairment	(4)	(95)	(187)
Valuation allowance, ending balance	0	209	251
Net carrying amount	8,884	$ 11,540	$ 11,687
Estimated Aggregate Amortization Expenses of Mortgage Servicing Rights [Abstract]
2016	1,300
2017	1,200
2018	1,000
2019	900
2020	$ 800

Estimated Aggregate Amortization Expenses of Mortgage Servicing Rights [Abstract]

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Mortgage Servicing Rights [Roll Forward]

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Servicing Asset, Net

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Servicing Asset at Amortized Value, Amount Capitalized

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount conveyed to unrelated parties of contract to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

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New provisions recoveries or charged against this account which increase or reduce the net value of servicing assets.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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