Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other comprehensive (loss) income, net of tax
Unrealized net holding (losses) gains arising during the period, pre-tax amounts	$ (2,471)	$ 12,757	$ (6,660)
Reclassification adjustment for net gains related to securities available for sale included in net income, pre-tax amounts	599	150	3,274
Amortization of prior service cost and actuarial gains, pre-tax amounts	3,593	1,665	1,768
Decrease in unrecognized actuarial loss, pre-tax amounts	$ (24)	$ (15,546)	$ (2,596)

Tax effect on adjustment out of other comprehensive income for prior service costs recognized as a component of net period benefit cost during the period.

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+ Details

- Definition

Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period.

+ References+ Details

- Definition

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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+ Details