Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$ (683)	$ 1,222	$ (3,325)
Tax expense (benefit) on net unrealized gains (losses) on investment securities available-for-sale	221	0	311
Tax expense on adjustment for pension and other postretirement benefits	$ (2,746)	$ 7,648	$ (9,344)