Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Total revenues	$ 236,912	$ 300,607	$ 191,664
Cost of revenues:
Total costs of revenues	140,453	160,846	109,600
Gross profit	96,459	139,761	82,064
Operating expenses:
Selling, general and administrative expenses	25,291	23,383	18,914
Research and development expenses	16,536	14,694	12,167
Bad debt expense	833	457	118
Total operating expenses	42,660	38,534	31,199
Income from operations	53,799	101,227	50,865
Other income (expense):
Interest expense	(471)	(260)	(199)
Interest income	123	880	743
Foreign exchange gains (losses)	182	(708)	457
Other, net	(90)	(46)	(4)
Total other income (expense), net	(256)	(134)	997
Income before income taxes	53,543	101,093	51,862
Income tax expense	16,632	31,536	16,744
Net income	36,911	69,557	35,118
Earnings per common share:
Basic	$ 2.82	$ 5.40	$ 2.76
Diluted	$ 2.81	$ 5.38	$ 2.74
Weighted average common shares outstanding:
Basic	12,950,958	12,886,372	12,735,520
Diluted	12,997,009	12,938,661	12,836,239
Products
Revenues:
Total revenues	209,581	287,233	175,378
Cost of revenues:
Total costs of revenues	125,497	152,659	103,789
Rental equipment
Revenues:
Total revenues	27,331	13,374	16,286
Cost of revenues:
Total costs of revenues	$ 14,956	$ 8,187	$ 5,811