SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE - Schedule of Repurchase Agreement Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Securities Sold Under Agreements To Repurchase [Line Items]
Securities Sold Under Agreements To Repurchase	$ 150,086	$ 300,000
Securities Sold Under Agreements To Repurchase Mature Three Months Or Less [Member]
Securities Sold Under Agreements To Repurchase [Line Items]
Securities Sold Under Agreements To Repurchase	50,086
Securities Sold Under Agreements To Repurchase Mature Three Year To Four Years [Member]
Securities Sold Under Agreements To Repurchase [Line Items]
Securities Sold Under Agreements To Repurchase	$ 100,000