Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Consolidated Balance Sheets [Abstract]
Capital stock, par value	$ 2	$ 2
Capital stock, shares authorized	20,000,000	10,000,000
Capital stock, shares issued	6,788,407	6,788,407
Prior service cost and unamortized net actuarial losses on employee benefit plans, tax	$ (225)	$ (249)
Net unrealized appreciation on securities available for sale, tax	4,936	2,828
Portion of OTTI attributable to non-credit gains, tax	216	249
Net unrealized depreciation on derivative instruments, tax	$ 1,123	$ 873
Treasury stock, shares	777,399	778,196