Bank segment (HEI only) Key Assumptions Used in Estimating the Fair Value of ASB's Mortgage Servicing Rights (Details) (Mortgage Servicing Rights (MSR), USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Prepayment rate:
25 basis points adverse rate change	$ (757)	$ (732)
50 basis points adverse change	(1,524)	(1,492)
Discount rate:
25 basis points adverse rate change	(140)	(154)
50 basis points adverse change	(278)	(306)
American Savings Bank (ASB)
Loans receivable
Unpaid principal balance	$ 1,391,030	$ 1,357,003
Weighted average note rate	4.07%	4.07%
Weighted average discount rate	9.60%	9.80%
Weighted average prepayment speed	9.50%	8.60%

Fair Value Inputs, Stated Interest Rate

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- Definition

Fair Value Inputs, Unpaid Principal Balance, Asset

+ References

No definition available.

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- Definition

The hypothetical financial impact of a 25 basis point adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 25 Basis Points Adverse Change in Discount Rate

+ References

No definition available.

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 50 Basis Point Adverse Change in Prepayment Speed

+ References

No definition available.

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 50 Basis Points Adverse Change in Discount Rate

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

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