Summary of Significant Accounting Policies - Property Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 5,813	$ 6,132
Accumulated depreciation	(3,514)	(3,749)
Property and equipment, net	2,299	2,383
Depreciation expense related to PP&E	922	966	$ 1,161
Furniture and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 4,748	4,600
Furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 876	1,040
Capitalized software costs
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 189	$ 492
Capitalized software costs | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Capitalized software costs | Maximum
Property, Plant and Equipment [Line Items]
Useful life	5 years