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Fair Value Measurements - Schedule of Investments Classified as Available for Sale Securities with Contractual Maturities (Details) - USD ($)
$ in Thousands
Dec. 31, 2019
Dec. 31, 2018
Fair Value Disclosures [Abstract]    
Cash and cash equivalents $ 57,937 $ 71,064
Short-term investments (due within one year) 130,333 185,480
Long-term investments (due between one and two years)   3,181
Total cash and investments in marketable securities $ 188,270 $ 259,725