General - Cash, Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 16,772	$ 10,712
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	16,772	10,712
Cash and cash equivalents \| Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,772	10,712
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	16,772	10,712
Marketable securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	28,072	34,113
Gross Unrealized Gains	8	4
Gross Unrealized Losses	0
Fair Value	28,080	34,117
Marketable securities \| US Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	28,072	34,113
Gross Unrealized Gains	8	4
Gross Unrealized Losses	0
Fair Value	28,080	34,117
Short-term deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	42,284	30,053
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	42,284	30,053
Short-term deposits \| Term bank deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	42,284	30,053
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 42,284	$ 30,053

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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