BUSINESS SEGMENTS (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segments	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Number of Operating Segments | segments			2
Net interest income	$ 29,992	$ 24,269	$ 82,555	$ 71,855
Noninterest income	8,831	7,535	24,021	21,246
Total income	38,823	31,804	106,576	93,101
Provision for loan and lease losses	400	2,100	4,200	6,000
Compensation and benefits	13,996	11,515	38,660	33,523
Premises and equipment expense	2,945	2,736	8,794	8,342
Other noninterest expense	4,437	3,101	12,035	10,328
Total noninterest expense	22,361	20,266	65,560	62,147
INCOME BEFORE INCOME TAX EXPENSE	16,462	11,538	41,016	30,954
Income tax expense	6,256	4,422	14,888	11,785
NET INCOME	10,206	7,116	26,128	19,169
Total assets at period end	4,176,332	3,774,383	4,176,332	3,774,383	$ 3,878,633
Banking [Member]
Net interest income	28,687	23,194	78,372	67,962
Noninterest income	2,928	2,974	7,975	7,286
Total income	31,615	26,168	86,347	75,248
Provision for loan and lease losses	400	2,100	4,200	6,000
Compensation and benefits	10,992	9,138	30,792	26,744
Premises and equipment expense	2,619	2,484	7,891	7,583
Other noninterest expense	3,167	2,688	8,559	10,047
Total noninterest expense	17,178	16,410	51,442	50,374
INCOME BEFORE INCOME TAX EXPENSE	14,437	9,758	34,905	24,874
Income tax expense	5,474	3,738	12,670	9,470
NET INCOME	8,963	6,020	22,235	15,404
Total assets at period end	4,148,222	3,729,004	4,148,222	3,729,004
Wealth Management Division [Member]
Net interest income	1,305	1,075	4,183	3,893
Noninterest income	5,903	4,561	16,046	13,960
Total income	7,208	5,636	20,229	17,853
Provision for loan and lease losses
Compensation and benefits	3,004	2,377	7,868	6,779
Premises and equipment expense	326	252	903	759
Other noninterest expense	1,853	1,227	5,347	4,235
Total noninterest expense	5,183	3,856	14,118	11,773
INCOME BEFORE INCOME TAX EXPENSE	2,025	1,780	6,111	6,080
Income tax expense	782	684	2,218	2,315
NET INCOME	1,243	1,096	3,893	3,765
Total assets at period end	28,110	45,379	28,110	45,379
Segments [Member]
Other noninterest expense	$ 5,020	$ 3,915	$ 13,906	$ 14,282