Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ 2,569	$ (1,335)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization expense	1,005	1,981
Stock-based compensation expense	903	801
Provision adjustments related to credit loss	6	111
Provision adjustments related to product warranty	171	49
Gain on disposal of property, plant and equipment	(29)	(1,602)
Other	(290)	(259)
Total non-cash adjustments	1,766	1,081
Changes in operating assets and liabilities:
Accounts receivable and contract assets	(970)	(1,450)
Inventory	(1,998)	(902)
Other assets	1,694	(2,809)
Accounts payable	836	794
Accrued expenses and other current liabilities	(2,371)	(1,358)
Total change in operating assets and liabilities	(2,809)	(5,725)
Net cash provided by (used in) operating activities	1,526	(5,979)
Cash flows from investing activities:
Purchase of equipment	(870)	(1,506)
Proceeds from disposal of property, plant and equipment	0	1,947
Net cash (used in) provided by investing activities	(870)	441
Cash flows from financing activities:
Net payments on credit facilities	0	(1,038)
Proceeds from exercise of equity awards	8	0
Taxes paid related to net share settlement of equity awards	(83)	(47)
Net cash used in financing activities	(75)	(1,085)
Effect of exchange rate changes provided by foreign currency	39	32
Net increase (decrease) in cash, cash equivalents and restricted cash	620	(6,591)
Cash, cash equivalents and restricted cash at beginning of period	30,538	21,977
Cash, cash equivalents and restricted cash at end of period	31,158	15,386
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid during the period for interest	15	47
NON-CASH INVESTING AND FINANCING ACTIVITIES
Changes in accounts payable related to purchases of equipment	$ (350)	$ (725)