Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Income Taxes
NOL and capital loss carryforwards	$ 69,252	$ 63,427
Tax credit carryforwards	23,779	21,221
Debt repurchase premium	18,221	20,297
Estimated liabilities	15,819	3,199
Stock-based compensation	9,306	9,365
Reserves and allowances	2,409	3,857
Convertible note hedge	1,279	4,796
Other	2,534	2,261
Valuation allowances	(127,795)	(104,531)
Total deferred tax assets	14,804	23,892
Property, plant and equipment basis differences	(11,066)	(9,834)
Goodwill and intangible asset basis differences	(2,381)	(8,589)
Convertible debt discount	(1,357)	(5,469)
Indefinite lived liabilities	(2,505)	(2,280)
Total deferred tax liabilities	(17,309)	(26,172)
Net deferred tax liability	$ (2,505)	$ (2,280)	$ 0