CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Revenues:
Product sales	$ 488,187	$ 348,387	$ 930,784	$ 696,124
Product sales to related party	14,585	13,118	30,143	27,841
Commissions	4,398	5,607	8,144	9,321
Total revenues	507,170	367,112	969,071	733,286
Cost of product sales	440,552	316,126	839,939	632,228
Gross profit	66,618	50,986	129,132	101,058
Selling, general and administrative expenses	42,933	32,450	81,840	63,497
Depreciation and amortization	2,274	1,667	4,466	3,156
Operating income	21,411	16,869	42,826	34,405
Other income (expense):
Interest expense	(252)	(252)	(435)	(434)
Earnings of equity method investees	79	63	156	136
Other	186	143	374	278
Total other income (expense), net	13	(46)	95	(20)
Income before taxes	21,424	16,823	42,921	34,385
Income tax expense	(8,246)	(6,491)	(16,547)	(13,225)
Net income	$ 13,178	$ 10,332	$ 26,374	$ 21,160
Earnings per common share
Basic	$ 1.04	$ 0.83	$ 2.09	$ 1.70
Diluted	$ 1.04	$ 0.83	$ 2.09	$ 1.69
Weighted average common shares outstanding:
Weighted Average Number of Shares Outstanding, Basic	12,619	12,462	12,600	12,438
Weighted Average Number of Shares Outstanding, Diluted	12,648	12,511	12,626	12,496