FAIR VALUE - Change in unrealized losses included in earnings (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Available-for-sale Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net impairment losses on available-for-sale investment securities credit component	[1]	$ (50)	$ 0	$ (387)

[1] Amounts mostly related to private label MBS.