LOANS AND ALLOWANCE FOR LOAN LOSSES - Aging Analysis of the Recorded Investment in Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	$ 12,049	$ 4,268
Nonaccrual Loans	13,913	15,788
Current Loans	2,175,578	1,871,579
Total loans evaluated for impairment	2,201,540	1,891,635
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	5,224	1,939
Nonaccrual Loans	5,031	3,896
Current Loans	435,774	410,917
Total loans evaluated for impairment	446,029	416,752
Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Nonaccrual Loans	0	0
Current Loans	83,577	67,038
Total loans evaluated for impairment	83,577	67,038
Real estate | Commercial real estate (including multi-family residential)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	2,736	1,661
Nonaccrual Loans	8,097	11,663
Current Loans	1,034,387	878,665
Total loans evaluated for impairment	1,045,220	891,989
Real estate | Commercial real estate construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,266	263
Nonaccrual Loans	0	0
Current Loans	224,308	158,984
Total loans evaluated for impairment	225,574	159,247
Real estate | 1-4 family residential (including home equity)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,012	280
Nonaccrual Loans	735	217
Current Loans	281,652	246,490
Total loans evaluated for impairment	283,399	246,987
Real estate | Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,779	0
Nonaccrual Loans	0	0
Current Loans	104,520	98,657
Total loans evaluated for impairment	106,299	98,657
Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	32	125
Nonaccrual Loans	50	12
Current Loans	11,360	10,828
Total loans evaluated for impairment	11,442	10,965
Financing Receivables, 30 to 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	12,049	3,357
Financing Receivables, 30 to 89 Days Past Due | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	5,224	1,028
Financing Receivables, 30 to 89 Days Past Due | Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, 30 to 89 Days Past Due | Real estate | Commercial real estate (including multi-family residential)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	2,736	1,661
Financing Receivables, 30 to 89 Days Past Due | Real estate | Commercial real estate construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,266	263
Financing Receivables, 30 to 89 Days Past Due | Real estate | 1-4 family residential (including home equity)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,012	280
Financing Receivables, 30 to 89 Days Past Due | Real estate | Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	1,779	0
Financing Receivables, 30 to 89 Days Past Due | Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	32	125
Financing Receivables, Equal to Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	911
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	911
Financing Receivables, Equal to Greater than 90 Days Past Due | Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real estate | Commercial real estate (including multi-family residential)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real estate | Commercial real estate construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real estate | 1-4 family residential (including home equity)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real estate | Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due | Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Past Due and Still Accruing	$ 0	$ 0