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INVESTMENT SECURITIES - Additional Information (Detail) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) position | Jun. 30, 2016 USD ($) | Jun. 30, 2017 position
Investment [Line Items] |  |  |
Percentage of debt securities considered to be of investment-grade | 98.00% |  | 98.00%
Maximum percentage of any general obligation bonds in one state |  |  | 8.00%
Percentage of tax exempt securities | 2.00% |  | 2.00%
Securities in unrealized loss positions, number of positions | 730 |  | 730
Number of positions | 2,260 |  | 2,260
Other-than-temporary impairments | $ | $ 0 | $ 0 |

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