Fair Value Inputs, Discount Rate [Abstract]

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Fair Value Inputs, Prepayment Rate [Abstract]

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Fair Value Inputs, Unpaid Principal Balance, Asset

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Mortgage Loans on Real Estate, Repurchase Reserve

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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.

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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

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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

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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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Servicing Asset, Accumulated Amortization

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Servicing Asset, Net

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Servicing Asset at Amortized Value, Amount Capitalized

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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.

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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.

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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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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.

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

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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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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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Value of input used to measure servicing asset.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount of increase (decrease) in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from expenses (recoveries) recognized.

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Bank segment - Mortgage servicing rights (Details) - American Savings Bank (ASB) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)
Servicing Asset at Amortized Cost [Line Items]
Repurchase reserve			$ 100		$ 100
Mortgage service fees	$ 900	$ 800
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Servicing asset - beginning balance	10,020
Servicing asset - ending balance	10,685
Residential loan
Servicing Asset at Amortized Cost [Line Items]
Proceeds from sale of mortgage loans	170,900	72,500
Gain on sale of mortgage loans	4,300	2,000
Servicing contracts
Changes in Carrying Value of MSRs
Gross carrying amount			20,830	$ 22,950
Accumulated amortization			(10,141)	(12,670)
Valuation allowance	(260)	0	(4)	(260)	0
Net carrying amount			10,685	10,020	$ 9,120
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Servicing asset - beginning balance	10,280	9,101
Amount capitalized	1,547	636
Amortization	(1,138)	(617)
Other-than-temporary impairment	0	0
Servicing asset - ending balance	10,689	9,120
Valuation Allowance [Roll Forward]
Valuation allowance, beginning balance	260	0
Provision (recovery)	(256)	0
Other-than-temporary impairment	0	0
Valuation allowance, ending balance	$ 4	$ 0
Unpaid principal balance			1,505,963	1,450,312
Prepayment rate:
25 basis points adverse rate change			(659)	(738)
50 basis points adverse rate change			(1,376)	(1,445)
Discount rate:
25 basis points adverse rate change			(110)	(68)
50 basis points adverse rate change			$ (218)	$ (135)
Servicing contracts \| Note rate
Valuation Allowance [Roll Forward]
Weighted average measurement input			0.0357	0.0368
Servicing contracts \| Discount rate
Valuation Allowance [Roll Forward]
Weighted average measurement input			0.0925	0.0925
Servicing contracts \| Prepayment speed
Valuation Allowance [Roll Forward]
Weighted average measurement input			0.120	0.177