Revenues - Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Unbilled receivable	$ 24,248	$ 20,663
ASUS
Disaggregation of Revenue [Line Items]
Unbilled receivable	10,661	10,125
Receivable from the U.S. government	96,044	85,456
Contract assets	14,008	14,982
Contract liabilities	$ 596	$ 903