ADVANCES FROM THE FEDERAL HOME LOAN BANK (FHLB) - Summary of Advances from FHLB (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Short Term Debt [Line Items]
Fixed-rate advances from FHLB, with a weighted-average interest rate of 1.69% (December 31, 2012 - 2.26%)	$ 675,000	$ 670,000
long term debt [member]
Short Term Debt [Line Items]
Fixed-rate advances from FHLB, with a weighted-average interest rate of 1.69% (December 31, 2012 - 2.26%)	665,000	500,000
short term debt [member]
Short Term Debt [Line Items]
Fixed-rate advances from FHLB, with a weighted-average interest rate of 1.69% (December 31, 2012 - 2.26%)	$ 10,000	$ 170,000