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No definition available.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Net number of non-option equity instruments granted to participants.

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Stock-based Compensation and Equity Grants - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Selling, General and Administrative Expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense		$ 2,608	$ 1,660
DLH Employees
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized expense for DLH employees (a)		$ 5,214	4,468
Weighted average period for recognition of compensation expense		4 years 2 months 12 days
DLH Employees \| Selling, General and Administrative Expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense		$ 1,960	1,193
Non-employee Directors \| Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Number of restricted stock units issued (in shares)	53,510
Number of restricted stocks vested in period (in shares)		53,510
Non-employee Directors \| Selling, General and Administrative Expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense		$ 648	$ 467
NEO \| Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Number of restricted stock units issued (in shares)		140,404
Number of restricted stock outstanding (in shares)		140,404