Earnings Per Share and Certain Related Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 23, 2015	Mar. 30, 2018	Mar. 31, 2017	Mar. 30, 2018	Mar. 31, 2017
Numerator for Basic and Diluted EPS:
Net income		$ 48,587,000	$ 50,018,000	$ 50,750,000	$ 110,554,000
Net income allocated to participating securities		(254,000)	(594,000)	(269,000)	(1,389,000)
Net income allocated to common stock for EPS calculation		$ 48,333,000	$ 49,424,000	$ 50,481,000	$ 109,165,000
Denominator for Basic and Diluted EPS:
Weighted average basic shares (in shares)		142,531,000	120,919,000	133,770,000	120,935,000
Shares allocated to participating securities (in shares)		(746,000)	(1,435,000)	(816,000)	(1,519,000)
Shares used for calculating basic EPS attributable to common stock (in shares)		141,785,000	119,484,000	132,954,000	119,416,000
Effect of dilutive securities:
Stock compensation plans (in shares)		1,048,000	795,000	1,035,000	866,000
Shares used for calculating diluted EPS attributable to common stock (in shares)		142,833,000	120,279,000	133,989,000	120,282,000
Basic (in dollars per share)		$ 0.34	$ 0.41	$ 0.38	$ 0.91
Diluted (in dollars per share)		$ 0.34	$ 0.41	$ 0.38	$ 0.91
Share Repurchases
Amount authorized to be repurchased	$ 500,000,000
Average cost per share repurchased (in dollars per share)	$ 60.77
Number of shares repurchased (in shares)	49,000