Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Other comprehensive income, net of tax:
Unrealized net holding gains arising during the period, pre-tax amounts	$ 13,211	$ 4,842
Reclassification adjustment for net gains related to securities available for sale included in net income, pre-tax amounts	29	14
Amortization of unrealized net gains and losses related to the reclassification of available for sale investment securities to held to maturity, pre-tax amounts	296	307
Amortization of prior service cost and actuarial loss, pre-tax amounts	$ 512	$ 561

Amount before tax, before reclassification adjustments, of unrealized holding gain (loss) related to transfers of securities into the held-to-maturity classification and out of the available-for-sale classification.

No definition available.

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Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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