CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Unrealized holding gains/ (losses), tax	$ (1,885)	$ (3,579)
Reclassification adjustment for gains included in net income, tax	43	1,218
Change in fair value of interest rate swaps, tax	(24)	(135)
Amortization of prior service costs included in net income, tax	$ (140)	$ 75

Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

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

+ References

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

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

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