Fair Value Measurements - Balance sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair value, balance sheet
Cash and cash equivalents	$ 27,399	$ 194,952
Available-For-Sale (Current)	87,693
Available-For-Sale (Non-Current)	40,712
Estimated Fair Value	147,583
Commercial paper
Fair value, balance sheet
Estimated Fair Value	30,966
Corporate notes / bonds
Fair value, balance sheet
Estimated Fair Value	43,760
Debt security
Fair value, balance sheet
Estimated Fair Value	1,000
Money market funds
Fair value, balance sheet
Estimated Fair Value	10,196
U.S. govt. agencies
Fair value, balance sheet
Estimated Fair Value	46,078
U.S. treasuries
Fair value, balance sheet
Estimated Fair Value	15,583
Recurring
Fair value, balance sheet
Cash and cash equivalents	19,178
Available-For-Sale (Current)	87,693
Available-For-Sale (Non-Current)	40,712
Estimated Fair Value	147,583
Recurring \| Commercial paper
Fair value, balance sheet
Available-For-Sale (Current)	30,966
Estimated Fair Value	30,966
Recurring \| Corporate notes / bonds
Fair value, balance sheet
Available-For-Sale (Current)	24,272
Available-For-Sale (Non-Current)	19,488
Estimated Fair Value	43,760
Recurring \| Debt security
Fair value, balance sheet
Available-For-Sale (Non-Current)	1,000
Estimated Fair Value	1,000
Recurring \| Money market funds
Fair value, balance sheet
Cash and cash equivalents	10,196
Estimated Fair Value	10,196
Recurring \| U.S. govt. agencies
Fair value, balance sheet
Cash and cash equivalents	8,982
Available-For-Sale (Current)	23,597
Available-For-Sale (Non-Current)	13,499
Estimated Fair Value	46,078
Recurring \| U.S. treasuries
Fair value, balance sheet
Available-For-Sale (Current)	8,858
Available-For-Sale (Non-Current)	6,725
Estimated Fair Value	$ 15,583

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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