Fair Value Measurements - Financial Assets Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial Assets:
Debt securities, available-for-sale	$ 31,416	$ 49,987
Level 1 | Fair Value, Recurring
Financial Assets:
Debt securities, available-for-sale	3,965	9,881
Total	87,461	66,439
Level 2 | Fair Value, Recurring
Financial Assets:
Debt securities, available-for-sale	27,451	40,106
Total	27,451	40,106
Level 3 | Fair Value, Recurring
Financial Assets:
Debt securities, available-for-sale	0	0
Total	0	0
Cash | Level 1 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	77,307	38,862
Cash | Level 2 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	0	0
Cash | Level 3 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	0	0
Money market mutual fund | Level 1 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	6,189	17,696
Money market mutual fund | Level 2 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	0	0
Money market mutual fund | Level 3 | Fair Value, Recurring
Financial Assets:
Cash and cash equivalents	$ 0	$ 0