Investments - Summary of Fair Value of Available for Sale Investments (Detail) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
---|---|---|
Schedule of Available-for-sale Securities [Line Items] | ||
Investments, Amortized Cost | $ 6,759 | $ 12,959 |
Investments, Gross Unrealized Gain | 8 | |
Investments, Fair Value | 6,759 | 12,967 |
Corporate Notes [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Investments, Amortized Cost | 5,489 | |
Investments, Gross Unrealized Gain | 2 | |
Investments, Fair Value | 5,491 | |
Treasury Bills [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Investments, Amortized Cost | 1,249 | |
Investments, Fair Value | 1,249 | |
Commercial Paper [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Investments, Amortized Cost | 1,999 | 7,470 |
Investments, Gross Unrealized Gain | 6 | |
Investments, Fair Value | 1,999 | $ 7,476 |
Agency Bonds [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Investments, Amortized Cost | 3,511 | |
Investments, Fair Value | $ 3,511 |