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Cash Equivalents and Marketable Securities - Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
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Cash Equivalents and Marketable Securities |  |
Total cash equivalents and marketable securities, Amortized Cost | $ 116,017 | $ 131,699
Total cash equivalents and marketable securities, Gross Unrealized Gains | 29 | 27
Total cash equivalents and marketable securities, Gross Unrealized Losses | (20) | (8)
Total cash equivalents and marketable securities, Fair Value | 116,026 | 131,718
Corporate debt securities |  |
Cash Equivalents and Marketable Securities |  |
Total cash equivalents and marketable securities, Amortized Cost | 13,289 | 33,653
Total cash equivalents and marketable securities, Gross Unrealized Gains | 2 | 11
Total cash equivalents and marketable securities, Gross Unrealized Losses | (3) | (2)
Total cash equivalents and marketable securities, Fair Value | 13,288 | 33,662
U.S. Treasury and agency securities |  |
Cash Equivalents and Marketable Securities |  |
Total cash equivalents and marketable securities, Amortized Cost | 17,508 | 40,798
Total cash equivalents and marketable securities, Gross Unrealized Gains | 24 | 14
Total cash equivalents and marketable securities, Gross Unrealized Losses | (1) | (2)
Total cash equivalents and marketable securities, Fair Value | 17,531 | 40,810
Money Market Funds |  |
Cash Equivalents and Marketable Securities |  |
Total cash equivalents and marketable securities, Amortized Cost | 45,644 | 12,964
Total cash equivalents and marketable securities, Fair Value | 45,644 | 12,964
Commercial Paper |  |
Cash Equivalents and Marketable Securities |  |
Total cash equivalents and marketable securities, Amortized Cost | 39,576 | 44,284
Total cash equivalents and marketable securities, Gross Unrealized Gains | 3 | 2
Total cash equivalents and marketable securities, Gross Unrealized Losses | (16) | (4)
Total cash equivalents and marketable securities, Fair Value | $ 39,563 | $ 44,282

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- Definition This item represents the cost of debt and equity securities, including cash equivalents which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as cash equivalents and marketable securities. + References No definition available. + Details
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