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Bank segment - Contingencies (Details) - USD ($) $ in Millions | Mar. 31, 2018 | Dec. 31, 2017
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American Savings Bank (ASB) |  |
Loss Contingencies [Line Items] |  |
Unfunded commitments to fund the company's LIHTC | $ 14.4 | $ 15.8

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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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Period Type: | instant

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- Details
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