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Bank segment - Contingencies (Details) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
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American Savings Bank (ASB) |  |
Loss Contingencies [Line Items] |  |
Unfunded commitments to fund the company's LIHTC | $ 62.8 | $ 62.8

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- Definition 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. + References No definition available. + Details
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Period Type: | duration

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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | credit
Period Type: | instant

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- Details
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Balance Type: |
Period Type: |