Income and other Taxes (Deferred Tax Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Federal net operating loss carryforwards	$ 147,449	$ 147,704
Foreign net operating loss carryforwards	51	66
Income tax credit carryforwards	3,062	3,033
Inventory reserves	2,614	2,283
Accrued warranty reserve	14	149
Accrued warranty reserve	328	587
State net operating loss carryforwards	7,009	9,527
Stock compensation	3,334	2,837
Deferred compensation	896	1,080
Fixed assets and intangibles	124	1,646
Other	728	1,388
Total deferred tax assets	165,609	170,300
Valuation allowance	(165,609)	(170,300)
Net deferred tax assets	$ 0	$ 0