Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Operating Activities:
Net income	$ 4,237	$ 1,123	$ 7,592
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,017	7,263	7,312
Stock-based compensation	5,863	5,453	5,077
Noncash lease expense	308	246
Provision for credit losses	(11)	73	160
Deferred taxes	1,651	(1,139)	(1,088)
Payment of contingent consideration obligations in excess of acquisition-date value		(608)	(2,041)
Losses (gains) on strategic investments		479	(7)
Acquired in-process research and development			890
Impairment losses on intangible assets			259
Other	181	5	(170)
Change in operating assets and liabilities
Accounts receivable and contract asset	(2,480)	3,461	(1,630)
Inventories	(818)	(1,377)	(543)
Prepaids and other	(2,391)	410	(2,131)
Accounts payable	264	(483)	(765)
Accrued liabilities	1,406	1,847	(2,187)
Income taxes	210	(1,558)	822
Deferred revenue	(1,048)	(1,185)	(3,512)
Net cash provided by operating activities	15,389	14,010	8,038
Investing Activities:
Purchases of property and equipment	(5,279)	(3,671)	(5,998)
Payment for acquisition of intangible assets	(1,000)
Purchases of available-for-sale securities	(22,723)	(59,917)	(44,973)
Sales and maturities of available-for-sale securities	43,317	54,522	61,458
Purchase of business, net of acquired cash	(39,553)
Acquisition of in-process research and development			(750)
Other			17
Net cash (used in) provided by investing activities	(25,238)	(9,066)	9,754
Financing Activities:
Proceeds from short-term borrowings	10,000
Issuance of common stock	3,128	1,615	723
Payments for taxes related to net share settlement of equity awards	(2,751)	(2,534)	(2,688)
Payment of deferred financing costs		(137)
Payments for acquisition of in-process research and development	(150)	(1,000)
Payment of contingent consideration obligations		(2,592)	(9,064)
Net cash provided by (used in) financing activities	10,227	(4,648)	(11,029)
Effect of exchange rate changes on cash	(10)	128	(70)
Net change in cash and cash equivalents	368	424	6,693
Cash and Cash Equivalents:
Beginning of year	30,785	30,361	23,668
End of year	31,153	30,785	30,361
Supplemental Information:
Cash paid for income taxes	160	30	193
Cash paid for interest	74
Noncash financing and investing activities:
Acquisition of property and equipment and intangible assets, net of refundable credits in other current assets and liabilities	211	1,306	202
Right-of-use assets and property and equipment obtained in exchange for new operating lease liabilities	234	$ 1,181
Deferred and contingent consideration assumed in business acquisition	$ 4,071
Acquisition of in-process research and development in other long-term liabilities			140
Accrual of employee taxes on common stock exercises			$ 104