LOAN SERVICING - Activity in SBA-Guaranteed Loan Servicing Asset (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Servicing Asset at Fair Value, Amount [Roll Forward]
SBA servicing fees	$ 33,610	$ 25,411	$ 91,806	$ 72,349
SBA-Guaranteed Loan Servicing [Member]
Servicing Assets at Fair Value [Line Items]
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance	50		50
Servicing Asset at Fair Value, Amount [Roll Forward]
SBA loans sold to investors with servicing retained	310,000		310,000
SBA loans sold with servicing retained	16,443		42,172
Gain from sale of SBA loan, pretax	964		1,780
SBA servicing fees	702		1,444
Balance at beginning of period	5,284		0
Fair value of servicing rights acquired	0		5,399
Additions	391		655
Impairment (charge) / recovery	(50)		(50)
Amortization	(342)		(721)
Balance at end of period	5,283		5,283
Loan servicing rights, fair value	$ 5,283		$ 5,283		$ 5,299	$ 0