Stock-based Compensation, Equity Grants, and Warrants - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Document Fiscal Year Focus	2017
Total compensation expense	$ 485	$ 332
Unrecognized stock-based compensation expense	20	112
DLH Employees
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized stock-based compensation expense	12	36
Non-employee Directors
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized stock-based compensation expense	8	76
Selling, General and Administrative Expenses | DLH Employees
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense	6	8
Selling, General and Administrative Expenses | Non-employee Directors
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense	479	324
Restricted Stock [Member] | Non-employee Directors
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation expense	$ 456	$ 304
Long Term Incentive Plan 2006 | Employee Stock Option
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Number of shares available for grant			0.9
Expiration term	10 years