Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total Revenue	$ 52,238	$ 33,752
Prime
Disaggregation of Revenue [Line Items]
Total Revenue	48,896	33,528
Subcontractor
Disaggregation of Revenue [Line Items]
Total Revenue	3,342	224
Time and materials
Disaggregation of Revenue [Line Items]
Total Revenue	36,441	32,790
Cost reimbursable
Disaggregation of Revenue [Line Items]
Total Revenue	14,617	609
Firm fixed price
Disaggregation of Revenue [Line Items]
Total Revenue	1,180	353
Department of Veterans Affairs
Disaggregation of Revenue [Line Items]
Total Revenue	24,063	22,811
Department of Health and Human Services
Disaggregation of Revenue [Line Items]
Total Revenue	24,089	10,267
Other
Disaggregation of Revenue [Line Items]
Total Revenue	$ 4,086	$ 674