ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY (Balance In The Allowance For Loan Losses And The Recorded Investment In Loans By Portfolio Management) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 3,801		$ 4,114
Collectively evaluated for impairment	41,696		39,604
Total ending allowance balance	45,497	$ 44,563	43,718	$ 42,853	$ 43,247	$ 43,610
Loans:
Loans individually evaluated for impairment	16,679		20,692
Loans collectively evaluated for impairment	3,618,573		3,450,235
Total ending loans balance	3,635,252		3,470,927
Commercial and Industrial Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	2,750		3,191
Collectively evaluated for impairment	17,177		17,081
Total ending allowance balance	19,927	20,219	20,272	20,320	20,935	21,564
Loans:
Loans individually evaluated for impairment	7,859		9,776
Loans collectively evaluated for impairment	1,354,186		1,258,682
Total ending loans balance	1,362,045		1,268,458
Commercial Real Estate and Multi-Family Residential Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	688		576
Collectively evaluated for impairment	13,759		12,876
Total ending allowance balance	14,447	13,775	13,452	12,973	12,637	12,473
Loans:
Loans individually evaluated for impairment	6,896		9,151
Loans collectively evaluated for impairment	1,401,366		1,290,131
Total ending loans balance	1,408,262		1,299,282
Agri Business and Agricultural Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	4,302		3,532
Total ending allowance balance	4,302	3,870	3,532	3,108	3,047	2,445
Loans:
Loans individually evaluated for impairment	310		283
Loans collectively evaluated for impairment	317,647		394,621
Total ending loans balance	317,957		394,904
Other Commercial [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	676		461
Total ending allowance balance	676	568	461	383	365	574
Loans:
Loans individually evaluated for impairment	0		0
Loans collectively evaluated for impairment	114,705		98,265
Total ending loans balance	114,705		98,265
Consumer 1-4 Family Mortgage Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	320		296
Collectively evaluated for impairment	2,370		2,531
Total ending allowance balance	2,690	2,689	2,827	2,851	2,934	3,395
Loans:
Loans individually evaluated for impairment	1,563		1,427
Loans collectively evaluated for impairment	363,361		347,408
Total ending loans balance	364,924		348,835
Other Consumer [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	43		51
Collectively evaluated for impairment	301		336
Total ending allowance balance	344	389	387	373	333	319
Loans:
Loans individually evaluated for impairment	51		55
Loans collectively evaluated for impairment	67,308		61,128
Total ending loans balance	67,359		61,183
Unallocated [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3,111		2,787
Total ending allowance balance	3,111	$ 3,053	2,787	$ 2,845	$ 2,996	$ 2,840
Loans:
Loans individually evaluated for impairment	0		0
Loans collectively evaluated for impairment	0		0
Total ending loans balance	$ 0		$ 0