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Proceeds From Sales and Calls of Debt Securities and Associates Gains or Losses (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Available-for-sale |  |  |
Proceeds from sales and calls of debt securities |  | $ 228,681 | $ 8,491
Gross realized gains | [1] | 6 | 10
Gross realized losses | [1] | (288) | (149)
Held-to-maturity |  |  |
Proceeds from calls of debt securities |  | 15,465 | 7,790
Gross realized gains | [1] | 54 | 81
Gross realized losses | [1] | $ (105) | $ (42)
[1] | The gain or loss on the sale or call of each debt security is determined by the specific identification method.

X
- Definition The total amount of proceeds received for the sale of securities categorized as held-to-maturity during the reporting period. The sale of held-to-maturity securities includes proceeds from maturities, prepayments and calls. + References No definition available. + Details
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- Definition This item represents the gain realized on the sale of held-to-maturity securities disposed of during the period. + References No definition available. + Details
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- Definition This item represents the loss realized on the sale of held-to-maturity securities disposed of during the period. Additionally, this item may include, if not separately presented, any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt securities which are being or have been recognized in earnings during the period. + References No definition available. + Details
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- References No definition available. + Details
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
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- Definition The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
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