Quarterly report pursuant to Section 13 or 15(d)

Cash Equivalents and Marketable Securities - Additional Information (Details)

v3.20.2
Cash Equivalents and Marketable Securities - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2019
Cash And Cash Equivalents [Line Items]          
Long-term marketable securities $ 5,647,000   $ 5,647,000   $ 15,609,000
Investments in an unrealized loss position 25,000,000.0   25,000,000.0   4,500,000
Unrealized losses 4,000   4,000   $ 3,000
Recognition of other-than-temporary impairment $ 0 $ 0 $ 0 $ 0  
Maximum          
Cash And Cash Equivalents [Line Items]          
Marketable securities maturity period     1 year   1 year