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MARKETABLE SECURITIES - Sale of Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Sale of Marketable Securities [Abstract] |  |  |  |
Proceeds | $ 199,974 | $ 31,969 | $ 214,736 | $ 109,056
Gross gains | 0 | 96 | 38 | 243
Gross losses | 0 | (32) | (13) | (161)
Held-to-maturity Securities, Sales, Excluding Other than Temporary Impairments [Abstract] |  |  |  |
Proceeds from sales | 0 | 0 | 923 | 1,866
Amortized cost | 0 | 0 | 907 | 1,842
Gross realized gains | 0 | 0 | 16 | 24
Tax expense related to securities gains/losses | $ 0 | $ 0 | $ (4) | $ (7)

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- Definition Held-to-maturity Securities, Sold Security, Amortized Cost + References No definition available. + Details
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- Definition Held-to-maturity Securities, Sold Security, Tax Expense (Benefit) On Realized Gain (Loss) + References No definition available. + Details
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- Definition Marketable Securities, Gross Realized Gains + References No definition available. + Details
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- Definition Marketable Securities, Gross Realized Losses + References No definition available. + Details
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- Definition Proceeds from the Sale of Marketable Securities + References No definition available. + Details
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- Definition Sale Of Marketable Securities [Abstract] + References No definition available. + Details
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- Definition This item represents the gain (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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563 + Details
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- Definition The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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