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Bank segment (HEI only) - Off Balance Sheet Arrangements and Additional Information (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
American Savings Bank (ASB) |  |
Guarantees |  |
FDIC insurance assessment | $ 2,600 | $ 3,200
American Savings Bank (ASB) | Indemnification Agreement |  |
Guarantees |  |
Accrued indemnification litigation obligation | 1,100 |
Reserve for Off-balance Sheet Activities |  |
Guarantees |  |
Unused Commitments to Extend Credit | 1,780,437 | 1,842,799
Home equity line of credit |  |
Guarantees |  |
Unused Commitments to Extend Credit | 1,214,103 | 1,146,339
Commercial and commercial real estate |  |
Guarantees |  |
Unused Commitments to Extend Credit | 466,510 | 577,410
Consumer |  |
Guarantees |  |
Unused Commitments to Extend Credit | 68,053 | 64,762
Residential 1-4 family |  |
Guarantees |  |
Unused Commitments to Extend Credit | 18,635 | 38,271
Commercial and financial standby letters of credit |  |
Guarantees |  |
Unused Commitments to Extend Credit | $ 13,136 | $ 16,017

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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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