Condensed Consolidated Statements of Operations (Unaudited) (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
Condensed Consolidated Statements of Operations [Abstract]
Revenues	$ 181,486	$ 125,111	$ 338,942	$ 249,785
Cost of goods sold	147,249	100,234	284,327	199,043
Gross profit	34,237	24,877	54,615	50,742
Selling, general and administrative expenses	21,523	21,538	41,286	42,466
Amortization of intangible assets	704	1,254	1,407	2,421
Operating income	12,010	2,085	11,922	5,855
Gain on sale of investment		(1,229)		(1,229)
Interest expense	68	94	144	208
Interest income	(34)	(62)	(63)	(107)
Income before income taxes	11,976	3,282	11,841	6,983
Income tax provision	4,565	1,549	6,175	2,818
Net income	$ 7,411	$ 1,733	$ 5,666	$ 4,165
Earnings per share:
Basic	$ 0.63	$ 0.15	$ 0.48	$ 0.36
Diluted	$ 0.63	$ 0.15	$ 0.48	$ 0.35
Weighted average shares:
Basic	11,762	11,666	11,765	11,653
Diluted	11,835	11,799	11,836	11,787