Stockholders' Equity and Stock Compensation Plans (Details 3) (USD $)	12 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 30, 2012
Stockholder's equity and stock compensation plans
Vesting period	1 year
Restricted Stock Program
Stock-based compensation expense	$ 10,374,000	$ 8,775,000	$ 10,839,000
Restricted Stock Program
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)		$ 24.32
Restricted Stock Program
Stock-based compensation expense	4,600,000	2,200,000	3,000,000
Unrecognized compensation cost	$ 10,500,000
Restricted Stock
Stockholder's equity and stock compensation plans
Initially granted (in shares)	117,067	108,350	105,567
Shares available for future award (in shares)	723,420
Number of Shares
Nonvested balance at the beginning of the period (in shares)	203,000
Granted (in shares)	117,000
Vested (in shares)	(3,000)
Forfeited (in shares)	(94,000)
Nonvested balance at the end of the period (in shares)	223,000	203,000
Vested or expected to vest at the end of the period (in shares)	223,000
Weighted-Average Grant Date Fair Value
Nonvested balance at the beginning of the period (in dollars per share)	$ 23.55
Granted (in dollars per share)	$ 28.58
Vested (in dollars per share)	$ 21.65
Forfeited (in dollars per share)	$ 23.44
Nonvested balance at the end of the period (in dollars per share)	$ 26.26	$ 23.55
Vested or expected to vest at the end of the period (in dollars per share)	$ 26.26
Performance-based restricted stock
Stockholder's equity and stock compensation plans
Period of growth in earnings per share considered to calculate percentage of shares vested	3 years
Additional shares awarded based on performance-based adjustments (in shares)		4,947	5,305
Base rate percentage for performance based adjustments		100.00%
Performance-based restricted stock | Minimum
Stockholder's equity and stock compensation plans
Percentage of shares that ultimately vest depending on fiscal year earnings per share growth rates	0.00%
Performance-based restricted stock | Maximum
Stockholder's equity and stock compensation plans
Percentage of shares that ultimately vest depending on fiscal year earnings per share growth rates	140.00%
RSUs
Stockholder's equity and stock compensation plans
Vesting period	4 years	4 years
Number of Shares
Nonvested balance at the beginning of the period (in shares)	333,140
Granted (in shares)	224,911	226,655
Vested (in shares)	(92,000)
Forfeited (in shares)	(34,000)
Nonvested balance at the end of the period (in shares)	432,289	333,140
Weighted-Average Grant Date Fair Value
Nonvested balance at the beginning of the period (in dollars per share)	$ 23.70
Granted (in dollars per share)	$ 28.53
Vested (in dollars per share)	$ 23.58
Forfeited (in dollars per share)	$ 25.58
Nonvested balance at the end of the period (in dollars per share)	$ 26.09	$ 23.70