GOODWILL AND OTHER INTANGIBLES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Jun. 30, 2012
Finite Lived Intangible Assets [Line Items]
Goodwill	$ 28,100		$ 28,100		$ 28,100
Purchase credit card relationship intangible amount						$ 24,500
Amortization expense			3,325	$ 3,669
Business Combination Finite Lived Intangible Assets Net	3,900		3,900
Purchased Credit Card Relationship Intangible [Member]
Finite Lived Intangible Assets [Line Items]
Purchase credit card relationship intangible amount	$ 24,465		24,465		$ 24,465
Amortization period of purchased credit card relationship intangible	4 years 2 months 12 days				5 years
Amortization expense	$ 600	$ 700	1,900	2,100
Core Deposits [Member]
Finite Lived Intangible Assets [Line Items]
Purchase credit card relationship intangible amount	$ 51,664		51,664		$ 51,664
Amortization period of purchased credit card relationship intangible	7 years 3 months 18 days				8 years 1 month 6 days
Amortization expense	$ 400	500	1,300	1,500
Customer Related Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Purchase credit card relationship intangible amount	$ 1,067		1,067		$ 1,067
Amortization period of purchased credit card relationship intangible	5 years 3 months 18 days				6 years 1 month 6 days
Amortization expense	$ 38	$ 38	$ 100	$ 100