RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES (Details)		3 Months Ended
	Jan. 01, 2019 USD ($) contract item	Mar. 31, 2019 USD ($) contract item
RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES
Practical expedient - package	true
Practical expedient - hindsight	true
Number of separate and distinct operating lease contracts to lease the land and/or buildings | contract	50
Number of offices where separate and distinct operating lease contracts to lease the land and/or buildings is held | item	38
Number of operating leases contracted with a related party of the Company | contract	15
Total operating lease liabilities		$ 40,203,000
Total right-of-use assets		$ 38,738,000
Number of operating leases considered variable | item		25
Number of lease contracts which had not commenced | contract		2
Number of banking centers where lease had not commenced | item		1
Number of LPOs where lease had not commenced | item		1
Operating lease liabilities		$ 600,000
Offsetting right-of-use assets		$ 600,000
ASU 2016-02 | Restatement
RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES
Total operating lease liabilities	$ 42,000,000
Total right-of-use assets	$ 40,000,000
Minimum
RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES
Expected remaining lease terms	9 months
Discounts rates	2.94%
Maximum
RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES
Expected remaining lease terms	18 years 6 months 4 days
Discounts rates	3.70%
Weighted Average
RIGHT-OF-USE ASSETS AND OPERATING LEASE LIABILITIES
Expected remaining lease terms	8 years 7 months 6 days
Discounts rates	3.48%