INCOME TAXES (Computation of Differences Between Financial Statement Tax Expense And Amounts) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income taxes at statutory federal rate of 35%									$ 27,026	$ 24,220	$ 23,167
Tax exempt income									(1,498)	(1,323)	(1,301)
Nondeductible expense									190	206	196
State income tax, net of federal tax effect									726	951	1,656
Captive insurance premium income									(361)	(363)	(378)
Tax credits									(311)	(241)	(233)
Bank owned life insurance									(554)	(605)	(631)
Reserve for unrecognized tax benefits									0	0	(64)
Other									(85)	(12)	(27)
Total income tax expense	$ 6,582	$ 6,498	$ 6,091	$ 5,962	$ 5,878	$ 5,841	$ 5,656	$ 5,458	$ 25,133	$ 22,833	$ 22,385