Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net unrealized gain (loss) on cash flow hedges, tax	$ (201)	$ 267	$ 140	$ 505
Net unrealized loss on investment securities, tax	(1,877)	1,249	(863)	2,453
Amortization of pension and postretirement costs, tax	$ 3,614	$ 3,613	$ 7,781	$ 7,254