Bank segment - Mortgage servicing rights (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
American Savings Bank (ASB)
Servicing Asset at Amortized Cost [Line Items]
Mortgage service fees	$ 900,000	$ 900,000
Movement in Mortgage Loans on Real Estate [Roll Forward]
Servicing Asset at Amortized Cost	11,540,000
Servicing Asset at Amortized Cost	11,965,000
American Savings Bank (ASB) \| Mortgage Servicing Rights (MSR)
Servicing Asset at Amortized Cost [Line Items]
Gross carrying amount	28,090,000	26,097,000
Accumulated amortization	(16,084,000)	(14,138,000)
Valuation allowance	(41,000)	(202,000)
Net carrying amount	11,965,000	11,757,000
Movement in Mortgage Loans on Real Estate [Roll Forward]
Servicing Asset at Amortized Cost	11,749,000	11,938,000
Servicing Asset at Amortized Value, Amount Capitalized	906,000	467,000
Servicing Asset at Amortized Cost, Amortization	(647,000)	(432,000)
Other-than-temporary impairment	(2,000)	(14,000)
Servicing Asset at Amortized Cost	12,006,000	11,959,000
Valuation Allowance [Roll Forward]
Valuation allowance, beginning balance	209,000	251,000
Provision (recovery)	(166,000)	(35,000)
Other-than-temporary impairment	(2,000)	(14,000)
Valuation allowance, ending balance	41,000	202,000
Unpaid principal balance	1,414,990,000	1,391,030,000
Weighted average note-rate	4.06%	4.07%
Weighted average discount rate	9.60%	9.60%
Weighted average prepayment speed	10.60%	9.50%
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 25 Basis Point Adverse Change in Prepayment Speed	(750,000)	(757,000)
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 50 Basis Point Adverse Change in Prepayment Speed	(1,408,000)	(1,524,000)
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 25 Basis Points Adverse Change in Discount Rate	(129,000)	(140,000)
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 50 Basis Points Adverse Change in Discount Rate	$ (256,000)	$ (278,000)
Troubled debt restructurings real estate loans
Servicing Asset at Amortized Cost [Line Items]
Financing Receivable Modifications Minimum, Period of Payment Default of Loans Determined to be Troubled Debt Restructurings	90 days

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

Represents the minimum period of payment default of loans determined to be troubled debt restructurings.

+ 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.

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

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- Definition

Servicing Asset, Accumulated Amortization

+ References

No definition available.

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- Definition

Servicing Asset at Amortized Value, Amount Capitalized

+ References

No definition available.

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- Definition

Servicing Asset, Net

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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)

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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.

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- Definition

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

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(6)

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 25

-Paragraph 1

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(4)

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

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-Subparagraph (e)(1)

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (e)(2)

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