Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Operating activities:
Net income	$ 2,357	$ 6,450
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation of property, equipment and improvements	656	724
Amortization of identifiable intangible assets	345	468
Stock-based compensation	1,173	816
Excess tax benefits from stock-based compensation	(183)	(190)
Deferred income tax provision	619	1,300
Gain on sale of business	0	(2,912)
Change in fair value of contingent consideration	(82)	0
Bad debt/product return provision	264	168
Inventory obsolescence	450	409
Restructuring charges	0	651
Other	(12)	40
Changes in operating assets and liabilities	(7,622)	(4,369)
Net cash (used in) provided by operating activities	(2,035)	3,555
Investing activities:
Purchase of marketable securities	(25,470)	(8,079)
Proceeds from maturities of marketable securities	32,155	7,106
Proceeds from sale of Etherios	3,000	2,866
Acquisition of business, net of cash acquired	(1,690)	(2,860)
Purchase of property, equipment, improvements and certain other identifiable intangible assets	(554)	(545)
Net cash provided by (used in) investing activities	7,441	(1,512)
Financing activities:
Acquisition earn-out payments	(518)	0
Excess tax benefits from stock-based compensation	183	190
Proceeds from stock option plan transactions	2,787	5,752
Proceeds from employee stock purchase plan transactions	297	301
Purchases of common stock	(390)	(403)
Net cash provided by financing activities	2,359	5,840
Effect of exchange rate changes on cash and cash equivalents	(2,350)	(711)
Net increase in cash and cash equivalents	5,415	7,172
Cash and cash equivalents, beginning of period	75,727	45,018
Cash and cash equivalents, end of period	81,142	52,190
Supplemental schedule of non-cash investing and financing activities
Receivable related to sale of Etherios	0	5,015
Liability related to acquisition of business	(1,300)	(10,550)
Accrual for purchase of property, equipment, improvements and certain other identifiable intangible assets	$ (105)	$ 0