Quarterly report pursuant to Section 13 or 15(d)

Nature of Business (Details)

v3.20.1
Nature of Business (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]          
Net Loss $ 17,226 $ 16,461 $ 75,400 $ 62,300 $ 54,000
Accumulated deficit (310,209)   $ (292,983)    
Cash equivalents and marketable securities $ 121,900