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MARKETABLE SECURITIES - Sale of Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Sale Of Marketable Securities [Abstract] |  |  |  |
Proceeds from sales | $ 0 | $ 102,356 | $ 3,957 | $ 111,813
Gross gains | 0 | 4 | 0 | 4
Gross losses | $ 0 | $ (3) | $ (22) | $ (54)

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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 Sale of Marketable Securities + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Sale Of Marketable Securities [Abstract] + References No definition available. + Details
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