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Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Other comprehensive income (loss), net of tax: |  |
Unrealized net holding (losses) gains arising during the period, pre-tax amounts | $ 836 | $ 13,211
Reclassification adjustment for net gains (losses) related to securities available for sale included in net income, pre-tax amounts | 0 | 29
Reclassification adjustment for an impairment write-down of equity security, pre-tax amounts | 1,312 | 0
Unrealized gains on derivatives (cash flow hedged) (pre-tax amounts) | 331 | 0
Amortization of unrealized net gains related to the reclassification of available for sale investment securities to held to maturity, pre-tax amounts | 238 | 296
Amortization of prior service cost and actuarial loss, pre-tax amounts | $ 435 | $ 512

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- Definition 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. + References No definition available. + Details
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- Definition Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e689-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580 + Details
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