CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Sales	$ 68,551	$ 76,420	$ 169,899	$ 154,171
Cost of sales	40,648	40,859	94,904	78,065
Gross profit	27,903	35,561	74,995	76,106
Operating expenses:
Selling, general and administrative	6,554	5,899	13,256	11,262
Research and development	5,097	3,768	9,472	7,133
Bad debt expense	296	338	644	607
Total operating expenses	11,947	10,005	23,372	19,002
Income from operations	15,956	25,556	51,623	57,104
Other income (expense):
Interest expense	(103)	(48)	(235)	(130)
Interest income	25	230	56	459
Foreign exchange gains (losses)	101	(714)	80	(668)
Other, net	(12)		(38)	(19)
Total other income (expense), net	11	(532)	(137)	(358)
Income before income taxes	15,967	25,024	51,486	56,746
Income tax expense	5,151	8,155	16,494	17,864
Net income	$ 10,816	$ 16,869	$ 34,992	$ 38,882
Basic earnings per share	$ 0.83	$ 1.31	$ 2.68	$ 3.02
Diluted earnings per share	$ 0.82	$ 1.30	$ 2.66	$ 3.01
Weighted average shares outstanding – Basic	12,950,416	12,882,396	12,948,788	12,854,858
Weighted average shares outstanding – Diluted	13,002,383	12,955,566	13,001,075	12,924,014