Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets:
Total financial assets	$ 22,955	$ 41,238
Treasury Bills
Financial Assets:
Total financial assets		7,490
Commercial Paper
Financial Assets:
Total financial assets		25,346
Level 1
Financial Assets:
Total financial assets	22,955	15,892
Level 1 | Treasury Bills
Financial Assets:
Total financial assets		7,490
Level 2
Financial Assets:
Total financial assets		25,346
Level 2 | Commercial Paper
Financial Assets:
Total financial assets		25,346
Cash and Money Markets
Financial Assets:
Total financial assets	22,595	8,042
Cash and Money Markets | Level 1
Financial Assets:
Total financial assets	22,595	8,042
Restricted Cash Money Market
Financial Assets:
Total financial assets	360	360
Restricted Cash Money Market | Level 1
Financial Assets:
Total financial assets	$ 360	$ 360