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Cash, Cash Equivalents and Short-Term Investments - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Cash Cash Equivalents And Short Term Investments [Line Items]    
Investment in continuous unrealized loss position for more than one year $ 0 $ 0
Maximum [Member]    
Cash Cash Equivalents And Short Term Investments [Line Items]    
Available for sale securities contractual maturity period 1 year