Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Sales	$ 300,607	$ 191,664	$ 172,970
Cost of sales	160,846	109,600	98,857
Gross profit	139,761	82,064	74,113
Operating expenses:
Selling, general and administrative expenses	23,383	18,914	18,051
Research and development expenses	14,694	12,167	11,529
Bad debt expense	457	118	128
Total operating expenses	38,534	31,199	29,708
Income from operations	101,227	50,865	44,405
Other income (expense):
Interest expense	(260)	(199)	(43)
Interest income	880	743	267
Foreign exchange gains (losses)	(708)	457	80
Other, net	(46)	(4)	(90)
Total other income (expense), net	(134)	997	214
Income before income taxes	101,093	51,862	44,619
Income tax expense	31,536	16,744	14,908
Net income	$ 69,557	$ 35,118	$ 29,711
Earnings per common share:
Basic	$ 5.40	$ 2.76	$ 2.39
Diluted	$ 5.38	$ 2.74	$ 2.36
Weighted average common shares outstanding:
Basic	12,886,372	12,735,520	12,441,313
Diluted	12,938,661	12,836,239	12,572,647