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Accumulated Other Comprehensive Income (Changes in AOCI by Component) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |  |
Beginning balance | [1] | $ 12,343 | $ 14,286 | $ (6,295) | $ 5,621
Other comprehensive income before reclassifications | [1] | 8,508 | (11,341) | 27,278 | (2,245)
Amounts reclassified from accumulated other comprehensive income (loss) | [1] | (40) | (156) | (172) | (587)
Net current-period other comprehensive income | [1] | 8,468 | (11,497) | 27,106 | (2,832)
Ending balance | [1] | 20,811 | 2,789 | 20,811 | 2,789
Unrealized Gains and Losses on Available-for-Sale Securities [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |  |
Beginning balance | [1] | 18,918 | 16,379 | 386 | 7,462
Other comprehensive income before reclassifications | [1] | 8,508 | (11,341) | 27,278 | (1,965)
Amounts reclassified from accumulated other comprehensive income (loss) | [1] | (146) | (219) | (384) | (678)
Net current-period other comprehensive income | [1] | 8,362 | (11,560) | 26,894 | (2,643)
Ending balance | [1] | 27,280 | 4,819 | 27,280 | 4,819
Unrealized Gains and Losses on Pension Plan Liability [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |  |
Beginning balance | [1] | (6,575) | (2,093) | (6,681) | (1,841)
Other comprehensive income before reclassifications | [1] | 0 | 0 | 0 | (280)
Amounts reclassified from accumulated other comprehensive income (loss) | [1] | 106 | 63 | 212 | 91
Net current-period other comprehensive income | [1] | 106 | 63 | 212 | (189)
Ending balance | [1] | $ (6,469) | $ (2,030) | $ (6,469) | $ (2,030)
[1] | All amounts are net of tax. Amounts in parenthesis indicate debits.

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- Definition Accumulated Other Comprehensive Income (Loss) [Roll Forward] + References No definition available. + Details
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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
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- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569643-111683 + Details
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