INCOME TAXES: (Details 2) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Other than temporary impairment	$ 5,411	$ 5,417
Net unrealized losses on retirement plans	12,007	16,068
Loan loss provisions	7,755	7,232
Deferred compensation	6,257	6,637
Compensated absences	917	894
Post-retirement benefits	2,026	2,014
Deferred loss on acquisition	1,177	1,377
Other	2,887	2,185
GROSS DEFERRED ASSETS	38,437	41,824
Deferred tax liabilities:
Net unrealized gains on securities available-for-sale	(5,234)	(5,831)
Depreciation	(2,632)	(2,423)
Mortgage servicing rights	(539)	(561)
Pensions	(424)	(2,182)
Intangibles	(2,283)	(1,652)
Other	(2,863)	(2,173)
GROSS DEFERRED LIABILITIES	(13,975)	(14,822)
NET DEFERRED TAX ASSETS (LIABILITIES)	$ 24,462	$ 27,002