Income Taxes Deferred tax assets and liabilities (Details) (USD $) In Thousands	Sep. 30, 2011	Oct. 01, 2010
Current: [Abstract]
Inventory	$ 4,181	$ 4,451
Bad debts	162	427
Accrued compensation and benefits	3,946	2,536
Product returns, allowances and warranty	1,222	572
Restructuring	515	794
Other - net	998	943
Current deferred tax assets	11,024	9,723
Less valuation allowance	(2,431)	(2,130)
Net current deferred tax assets	8,593	7,593
Long-term: [Abstract]
Intangible assets	7,660	9,422
Retirement benefits and deferred compensation	27,921	21,327
Net operating loss carry forwards	22,143	6,120
Federal tax credits	37,717	28,243
State investement credits	26,111	24,173
Long-term deferred tax assets	121,552	89,285
Less valuation allowance	(36,943)	(23,480)
Net long-term deferred tax assets	84,609	65,805
Deferred tax assets	132,576	99,008
Less valuation allowance	(39,374)	(25,610)
Net deferred tax assets	93,202	73,398
Deferred Tax Liabilities [Abstract]
Prepaid insurance	(723)	(724)
Current deferred tax liabilities	(723)	(724)
Property, plant and equipment	(18,084)	(4,636)
Other - net	(208)	(272)
Intangible assets	(5,943)	(329)
Long-term deferred tax liabilities	(24,235)	(5,237)
Net deferred tax liabilities	24,958	5,961
Total deferred tax assets	$ 68,244	$ 67,437