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Investments and Fair Value Measurements - Schedule of Investments (Detail) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Held-to-Maturity debt instruments | $ 23,689 | $ 13,990
Federal Agency [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Held-to-Maturity debt instruments | $ 23,689 | $ 13,990

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- Definition Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References No definition available. + Details
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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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- Details
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