Investments - Summary of Available-for-Sale Investments at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Cost		$ 4,499
Estimated Fair Value	$ 0	4,499
Short-term investments - commercial paper
Schedule of Available-for-sale Securities
Cost		3,499
Estimated Fair Value		3,499
US Treasury Bill Securities [Member]
Schedule of Available-for-sale Securities
Cost		1,000
Estimated Fair Value		$ 1,000