Marketable Securities - Gross Unrealized Losses and Fair Value of Available-For-Sale Debt Securities (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Fair Value	$ 10,789
Unrealized Losses	29
Corporate bonds
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Fair Value	8,371
Unrealized Losses	24
Government securities - U.S.
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Fair Value	267
Unrealized Losses	1
Other fixed-income securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Fair Value	2,151
Unrealized Losses	$ 4