Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Operating Activities:
Net income	$ 620,327	$ 1,045,940
Adjustments to reconcile net income to net cash used in operating activities
Depreciation and amortization	208,537	201,267
Warranty provision	(19,516)	20,618
Inventory obsolescence	94,415	54,854
Share-based compensation	158,327	133,845
Deferred income taxes	172,390	283,003
Amortization of operating lease right of use asset	145,382
Changes in operating assets and liabilities:
Accounts receivable, net	(2,286,618)	(5,916,242)
Inventories, net	(320,998)	(2,029,403)
Prepaid expenses and other	760,823	2,136,282
Accounts payable	604,134	(66,849)
Accrued and other liabilities	(1,918,180)	(957,199)
Net cash used in operating activities	(1,780,977)	(5,093,884)
Investing Activities:
Purchases of marketable securities	(639,794)	(874,353)
Proceeds from maturities of marketable securities	588,749	982,834
Capital expenditures	(86,159)	(38,813)
Net cash (used in) provided by investing activities	(137,204)	69,668
Financing Activities:
Proceeds from exercise of stock options	144,214	2,528
Repurchase of common stock		(1,621,022)
Net cash provided by (used in) financing activities	144,214	(1,618,494)
Effect of foreign exchange rate on cash	14,336	(9,734)
Net decrease in cash, cash equivalents, and restricted cash	(1,759,631)	(6,652,444)
Cash, cash equivalents and restricted cash, beginning of period	19,516,918	11,806,074	$ 11,806,074
Cash, cash equivalents and restricted cash, end of period	17,757,287	5,153,630	19,516,918
Cash and cash equivalents				$ 17,092,203	$ 18,819,078	$ 4,416,106
Restricted cash, current portion				269,830		397,933
Long-term restricted cash				395,254		339,591
Total cash, cash equivalents and restricted cash shown in the consolidated statement of cash flows	17,757,287	5,153,630	$ 11,806,074	$ 17,757,287	$ 19,516,918	$ 5,153,630
Noncash investing and financing activities:
Change in unrealized loss on marketable securities	(3,486)	(613)
Initial measurement of operating lease right of use assets and liabilities	$ 7,814,701