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Investments - Additional Information (Detail) - Maximum [Member] | 9 Months Ended
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Sep. 30, 2015
Schedule of Available-for-sale Securities [Line Items] |
Investment securities maturity period or average life | 3 years
Average duration of portfolio | 1 year

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- Definition Investment Securities Maturity Period + References No definition available. + Details
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- Definition Weighted Average Duration Investment Securities Portfolio + References No definition available. + Details
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Balance Type: | na
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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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Period Type: |