Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other comprehensive (loss) income, net of tax
Unrealized net holding (losses) gains arising during the period, pre-tax amounts	$ (3,693)	$ (6,927)	$ 13,199	$ (33,391)
Reclassification adjustment for net gains related to securities available for sale included in net income, pre-tax amounts	38	329	58	1,413
Amortization of unrealized net gains and losses related to the reclassification of available for sale investment securities to held to maturity, pre-tax amounts	99	0	99	0
Amortization of prior service cost and actuarial gains, pre-tax amounts	19	709	57	2,244
Increase in unrecognized actuarial gains, pre-tax amounts	$ 0	$ 4,036	$ 0	$ 4,036