Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other comprehensive (loss) income, before tax
Unrealized net holding (losses) gains arising during the period, pre-tax amounts	$ 8,267	$ (24,712)	$ 16,892	$ (26,464)
Reclassification adjustment for net gains related to securities available for sale included in net income, pre-tax amounts	14	(61)	21	1,084
Amortization of prior service cost and actuarial gains, pre-tax amounts	$ 19	$ 710	$ 38	$ 1,536