Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Components of accumulated other comprehensive loss, net of related tax benefit/expense
Net unrealized gains on investment securities – available-for-sale, net of related tax expense of $2,542 at September 30, 2012, $1,796 at December 31, 2011 and $1,925 at September 30, 2011	$ 4,721	$ 3,336	$ 3,576
Pension and other postretirement benefits adjustment, net of related tax benefit of $14,876 at September 30, 2012, $15,435 at December 31, 2011 and $9,195 at September 30, 2011	(27,627)	(28,665)	(17,077)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total	$ (22,906)	$ (25,329)	$ (13,501)