Stockholders' Equity and Stock Compensation Plans (Details 4) (USD $)	12 Months Ended												3 Months Ended	12 Months Ended
	Sep. 30, 2012	Oct. 02, 2011	Oct. 03, 2010	Sep. 30, 2012 Restricted Stock Program Y	Oct. 02, 2011 Restricted Stock Program	Oct. 03, 2010 Restricted Stock Program	Sep. 30, 2012 Performance-based restricted stock	Oct. 02, 2011 Performance-based restricted stock	Oct. 03, 2010 Performance-based restricted stock	Sep. 30, 2012 Performance-based restricted stock Minimum	Sep. 30, 2012 Performance-based restricted stock Maximum	Sep. 30, 2012 Time-based restricted stock	Dec. 31, 2011 Restricted stock units (RSU's)	Sep. 30, 2012 Restricted stock units (RSU's)
Stockholder's Equity and Stock Compensation Plans
Vesting period (in years)												3 years		4 years
Period of growth in earnings per share considered to calculate percentage of shares vested (in years)				3
Additional shares awarded based on performance-based adjustments (in shares)							5,305	8,356	11,557
Shares available for future award (in shares)				1,251,518
Percentage of shares that ultimately vests depending on fiscal year earnings per share growth rates										0.00%	140.00%
Base rate percentage for performance based adjustments							100.00%
Number of Shares
Nonvested balance at the beginning of the period (in shares)				174,000
Granted (in shares)				111,000									181,348	181,000
Initially granted (in shares)				105,567	94,606	88,258
Granted to date (in shares)				288,431			278,431					10,000
Vested (in shares)				(89,000)
Forfeited (in shares)				(6,000)										(9,000)
Nonvested balance at the end of the period (in shares)				190,000	174,000									171,967
Vested or expected to vest at the end of the period (in shares)				190,000
Weighted-Average Grant Date Fair Value
Nonvested balance at the beginning of the period (in dollars per share)				$ 23.14
Granted (in dollars per share)				$ 22.53									$ 22.53	$ 22.53
Vested (in dollars per share)				$ 22.44
Forfeited (in dollars per share)				$ 24.30										$ 22.53
Nonvested balance at the end of the period (in dollars per share)				$ 23.08	$ 23.14									$ 22.53
Vested or expected to vest at the end of the period (in dollars per share)				$ 23.08
Restricted Stock Program
Unrecognized compensation cost				$ 2,500,000
Stock-based compensation expense	$ 10,839,000	$ 10,582,000	$ 10,178,000	$ 2,200,000	$ 1,700,000	$ 1,200,000