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Organization and Basis of Presentation - Basis of Presentation (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2022 | Dec. 31, 2021
Capitalization |  |  |
Investment securities comprised of collateralized loan obligations rated AA or better and obligations issued by local state and political subdivisions rated AA or better |  | 4.00% | 4.00%
Credit losses recognized on securities | $ 0 | $ 0 | $ 0
First Hawaiian, Inc. (FHI) |  |  |
Capitalization |  |  |
Outstanding common stock owned (as a percent) | 100.00% | 100.00% |

X
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- Definition Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 9 -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455 + Details
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- Details
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