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	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 2,813		$ 3,216
Collectively evaluated for impairment	44,893		43,905
Total ending allowance balance	47,706	$ 45,627	47,121	$ 44,563	$ 43,774	$ 43,718
Loans:
Loans individually evaluated for impairment	16,936		13,870
Loans collectively evaluated for impairment	3,841,777		3,804,589
Total ending loans balance	3,858,713		3,818,459
Commercial and industrial loans:
Ending allowance balance attributable to loans:
Individually evaluated for impairment	2,046		2,067
Collectively evaluated for impairment	20,478		19,030
Total ending allowance balance	22,524	20,725	21,097	20,219	19,781	20,272
Loans:
Loans individually evaluated for impairment	10,603		6,979
Loans collectively evaluated for impairment	1,461,326		1,411,648
Total ending loans balance	1,471,929		1,418,627
Commercial Real Estate and MultiFamily Residential Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	536		795
Collectively evaluated for impairment	14,418		13,919
Total ending allowance balance	14,954	14,438	14,714	13,775	13,718	13,452
Loans:
Loans individually evaluated for impairment	4,291		4,802
Loans collectively evaluated for impairment	1,503,794		1,438,219
Total ending loans balance	1,508,085		1,443,021
Agri-business and Agricultural Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	4,585		4,920
Total ending allowance balance	4,585	4,848	4,920	3,870	3,459	3,532
Loans:
Loans individually evaluated for impairment	283		283
Loans collectively evaluated for impairment	304,033		382,643
Total ending loans balance	304,316		382,926
Other Commercial [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	464		577
Total ending allowance balance	464	510	577	568	545	461
Loans:
Loans individually evaluated for impairment	0		0
Loans collectively evaluated for impairment	120,395		123,922
Total ending loans balance	120,395		123,922
Consumer 1-4 Family Mortgage Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	205		310
Collectively evaluated for impairment	1,748		2,458
Total ending allowance balance	1,953	2,018	2,768	2,689	2,790	2,827
Loans:
Loans individually evaluated for impairment	1,712		1,756
Loans collectively evaluated for impairment	372,394		374,013
Total ending loans balance	374,106		375,769
Other Consumer [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	26		44
Collectively evaluated for impairment	240		335
Total ending allowance balance	266	245	379	389	379	387
Loans:
Loans individually evaluated for impairment	47		50
Loans collectively evaluated for impairment	79,835		74,144
Total ending loans balance	79,882		74,194
Unallocated [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,960		2,666
Total ending allowance balance	2,960	$ 2,843	2,666	$ 3,053	$ 3,102	$ 2,787
Loans:
Loans individually evaluated for impairment	0		0
Loans collectively evaluated for impairment	0		0
Total ending loans balance	$ 0		$ 0