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Fair Value of Financial Instruments - Additional Information (Detail)
3 Months Ended 12 Months Ended
Mar. 31, 2020
Dec. 31, 2019
Available-for-sale Securities [Member] | Certificates of Deposit [Member] | Maximum [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Financial instruments maturity period 13 months 13 months