Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Sep. 28, 2013	Sep. 29, 2012
Schedule Of Income Taxes [Line Items]
State tax net operating losses	$ 94,900,000
Foreign losses	2,400,000
Federal income tax credits	1,400,000
State income tax credits	3,700,000
Valuation allowances	6,968,000	7,282,000
Period of uncertain tax positions as non-current income tax liabilities unless expected to be paid	1 year
Penalties were accrued related to uncertain tax positions	0	0
Unrecognized tax benefit may be recognized within twelve months as a result of a settlement	400,000
Maximum [Member]
Schedule Of Income Taxes [Line Items]
State tax net operating losses expiration year	2033
Federal income tax credits expiration year	2033
State income tax credits expiration year	2029
Accrued interest	$ 100,000	$ 100,000
Minimum [Member]
Schedule Of Income Taxes [Line Items]
State tax net operating losses expiration year	2013
Federal income tax credits expiration year	2023
State income tax credits expiration year	2013