Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2011
Valuation Account - Doubtful Accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 295		$ 339		$ 549
Increase (Decrease) to costs and expenses	309		418		(96)
Deductions	291	[1]	462	[1]	114	[1]
Balance at end of period	313		295		339
Reserve for Future Returns and Pricing Adjustments
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	1,362		1,280		1,106
Increase (Decrease) to costs and expenses	6,973		4,881		5,156
Deductions	6,565		4,799		4,982
Balance at end of period	$ 1,770		$ 1,362		$ 1,280

[1] Uncollectible accounts charged against allowance, net of recoveries