CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Revenues:
Product sales	$ 1,489,500	$ 1,169,545	$ 880,703
Product sales to related party	55,185	43,017	46,406
Commissions	20,655	16,780	14,223
Total revenues	1,565,340	1,229,342	941,332
Cost of product sales	1,359,755	1,064,339	806,677
Gross profit	205,585	165,003	134,655
Selling, general and administrative expenses	130,656	105,793	90,827
Depreciation and amortization	6,263	4,992	3,365
Operating income	68,666	54,218	40,463
Other income (expense):
Interest expense	(741)	(539)	(242)
Earnings of equity method investees	268	220	230
Other	507	427	540
Total other income (expense), net	34	108	528
Income before taxes	68,700	54,326	40,991
Income tax expense	(26,120)	(20,886)	(16,086)
Net income	$ 42,580	$ 33,440	$ 24,905
Earnings per common share
Basic	$ 3.42	$ 2.73	$ 2.06
Diluted	$ 3.40	$ 2.70	$ 2.02
Weighted average common shares outstanding:
Weighted Average Number of Shares Outstanding, Basic	12,464	12,241	12,088
Weighted Average Number of Shares Outstanding, Diluted	12,513	12,395	12,306