Selected Quarterly Financial Information (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	0 Months Ended	1 Months Ended	3 Months Ended								12 Months Ended
	Mar. 28, 2011	May 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Quarterly Financial Data [Abstract]
Revenue			$ 47,488	$ 41,062	$ 37,780	$ 37,451	$ 52,123	$ 49,480	$ 47,218	$ 52,107	$ 163,781	$ 200,928	$ 191,278
Cost of revenue			42,891	36,677	32,404	33,983	42,090	40,010	36,638	39,427	145,955	158,165	140,617
Gross profit			4,597	4,385	5,376	3,468	10,033	9,470	10,580	12,680	17,826	42,763	50,661
Operating expenses (income):
Selling, general, and administrative			10,258	8,758	8,365	7,480	8,281	9,657	9,380	8,264	34,861	35,582	42,549
Research and development			4,581	4,996	5,781	6,980	8,129	9,549	7,984	7,191	22,338	32,853	29,538
Impairments			0	1,425	0	0	8,000	0	0	0	1,425	8,000	0
Flood-related loss (recovery)			0	(293)	114	5,698					5,519	0	0
Flood-related insurance proceeds			(4,000)	0	0	(5,000)					(9,000)	0	0
(Gain) loss on sale of assets			51	(2,793)	0	0					(2,742)	0	0
Litigation settlements, net	(2,600)	1,000	0	1,050	0	0	(20)	1,465	(2,590)	0	1,050	(1,145)	0
Total operating expense			10,890	13,143	14,260	15,158	24,390	20,671	14,774	15,455	53,451	75,290	72,087
Operating loss			(6,293)	(8,758)	(8,884)	(11,690)	(14,357)	(11,201)	(4,194)	(2,775)	(35,625)	(32,527)	(21,426)
Other income (expense):
Interest expense, net			(281)	(146)	(121)	(129)	(120)	(132)	(130)	(258)	(677)	(640)	(415)
Foreign exchange gain (loss)			(15)	(196)	167	89	(304)	625	749	(335)	45	735	(1,008)
Loss from equity method investment			0	0	(241)	(960)	(996)	(259)	(587)	0	(1,201)	(1,842)	0
Change in fair value of financial instruments			21	61	(256)	105	1,487	(107)	(1,038)	(272)	(69)	70	(475)
Other expense			0	0	0	0	0	(5)	(5)	(5)	0	(15)	(370)
Total other income (expense)			(275)	(281)	(451)	(895)	67	122	(1,011)	(870)	(1,902)	(1,692)	(2,268)
Loss before income tax expense			(6,568)	(9,039)	(9,335)	(12,585)	(14,290)	(11,079)	(5,205)	(3,645)	(37,527)	(34,219)	(23,694)
Foreign income tax expense on capital distributions			0	0	0	(1,644)	0	0	0	0	(1,644)	0	0
Net loss			$ (6,568)	$ (9,039)	$ (9,335)	$ (14,229)	$ (14,290)	$ (11,079)	$ (5,205)	$ (3,645)	$ (39,171)	$ (34,219)	$ (23,694)
Per share data:
Net loss per basic and diluted share (in dollars per share)			$ (0.27)	$ (0.38)	$ (0.40)	$ (0.61)	$ (0.61)	$ (0.49)	$ (0.24)	$ (0.17)
Weighted-average number of basic and diluted shares outstanding			23,892	23,686	23,529	23,476	23,326	22,461	21,804	21,313