Bank segment (HEI only) Mortgage Servicing Rights- Narrative (Details) - American Savings Bank (ASB) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loans receivable
Repurchased mortgage loans	$ 0.0	$ 0.5	$ 1.9
Mortgage servicing fees	$ 3.5	3.5	3.3
Minimum
Loans receivable
Servicing Assets and servicing liabilities, basis spread	0.50%
Maximum
Loans receivable
Servicing Assets and servicing liabilities, basis spread	1.00%
Residential loan
Loans receivable
Proceeds from sale of mortgage loans	$ 275.3	155.0	273.8
Gain on sale of mortgage loans	$ 6.3	$ 2.9	$ 8.3

Mortgage Loans on Real Estate, Repurchases

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- Definition

Risks Inherent in Servicing Assets and Servicing Liabilities, Basis Spread

+ References

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+ References

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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

+ References

No definition available.

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3461-108585

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