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The number of vested or expected to vest equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Stockholders' Equity and Stock Compensation Plans (Details 4) (USD $)	12 Months Ended
	Oct. 02, 2011	Oct. 03, 2010	Sep. 27, 2009
Number of Shares
Nonvested balance at the beginning of the period (in shares)	166,375
Nonvested balance at the end of the period (in shares)	174,175	166,375
Restricted Stock Program
Stock-based compensation expense	$ 10,582,000	$ 10,178,000	$ 9,392,000
Restricted Stock Program
Stockholder's Equity and Stock Compensation Plans
Period of growth in earnings per share considered to calculate percentage of shares vested (in years)	3
Shares available for future award (in shares)	528,403
Number of Shares
Nonvested balance at the beginning of the period (in shares)	166,000
Granted (in shares)	103,000
Initially granted (in shares)	94,606	88,258	72,200
Granted to date (in shares)	255,064
Vested (in shares)	(56,000)
Forfeited (in shares)	(39,000)
Nonvested balance at the end of the period (in shares)	174,000	166,000
Vested or expected to vest at the end of the period (in shares)	174,000
Weighted-Average Grant Date Fair Value
Nonvested balance at the beginning of the period (in dollars per share)	$ 22.70
Granted (in dollars per share)	$ 23.32
Vested (in dollars per share)	$ 20.88
Forfeited (in dollars per share)	$ 24.93
Nonvested balance at the end of the period (in dollars per share)	$ 23.14	$ 22.70
Vested or expected to vest at the end of the period (in dollars per share)	$ 23.14
Restricted Stock Program
Unrecognized compensation cost	2,600,000
Stock-based compensation expense	$ 1,700,000	$ 1,200,000	$ 2,000,000
Performance-based restricted stock
Stockholder's Equity and Stock Compensation Plans
Additional shares awarded based on performance-based adjustments (in shares)	8,356	11,557	7,408
Number of Shares
Granted to date (in shares)	235,064
Time-based restricted stock
Stockholder's Equity and Stock Compensation Plans
Vesting period (in years)	4Y
Number of Shares
Granted to date (in shares)	20,000