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Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Other comprehensive income, net of tax: |  |  |  |
Unrealized net holding gains arising during the period, pre-tax amounts | $ 2,528 | $ 3,730 | $ 3,364 | $ 16,941
Reclassification adjustment for net (gains) related to securities available for sale included in net income, pre-tax amounts | 2 | 1 | 2 | 30
Reclassification adjustment for an impairment write-down of equity security, pre-tax amounts | 0 | 0 | 1,312 | 0
Unrealized loss on derivatives (cash flow hedged) (pre-tax amounts) | (434) | (62) | (104) | (62)
Amortization of unrealized net gains related to the reclassification of available for sale investment securities to held to maturity, pre-tax amounts | 225 | 280 | 463 | 576
Amortization of prior service cost and actuarial loss, pre-tax amounts | $ 435 | $ 513 | $ 870 | $ 1,024

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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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- Definition Amount before tax 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 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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