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Fair Value Measurements - Additional Information (Details) - USD ($)
Mar. 31, 2020
Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]    
Fair value assets transfers between levels amount $ 0  
Corporate [Member]    
Schedule Of Available For Sale Securities [Line Items]    
Available for sale securities aggregate market value 0 $ 0
Level 2 [Member] | Corporate [Member]    
Schedule Of Available For Sale Securities [Line Items]    
Available For sale securities continuous unrealized loss position twelve months or more amortized historical cost basis 4,700,000  
Available for sale securities aggregate market value $ 4,900,000