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Other Investments - Additional Information (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Other Investments Disclosure [Abstract] |  |
Other investments | $ 24,400 | $ 29,837

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- Definition Other Investments Disclosure [Abstract] + References No definition available. + Details
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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809 + Details
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