PARENT COMPANY CONDENSED FINANCIAL STATEMENTS: (Details 1) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Income tax benefit									$ (20,622)	$ (19,883)	$ (10,392)
NET INCOME	$ 2,616	$ 8,794	$ 8,352	$ 9,369	$ 8,344	$ 8,162	$ 8,232	$ 13,675	29,131	38,413	30,196
Comprehensive Income (Loss), Net of Tax, Attributable to Parent									28,591	33,650	35,324
Parent
Condensed Financial Statements, Captions [Line Items]
Dividends from subsidiaries									30,814	31,781	19,397
Other income									720	722	795
Other operating expenses									(2,647)	(2,581)	(2,314)
Income before income taxes and equity in undistributed earnings of subsidiaries									28,887	29,922	17,878
Income tax benefit									889	821	815
Income before equity in undistributed earnings of subsidiaries									29,776	30,743	18,693
Equity in undistributed earnings of subsidiaries									(645)	7,670	11,503
NET INCOME									$ 29,131	$ 38,413	$ 30,196