Investment Securities - Additional Information (Details) - Securities	Jun. 30, 2016	Dec. 31, 2015
Investments Debt And Equity Securities [Abstract]
Number of investment securities with fair values less than amortized cost	80	234

Available-for-sale and held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions

No definition available.

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant