Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended			6 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Sep. 26, 2015	Dec. 30, 2017	Dec. 31, 2016	Jul. 01, 2017	Mar. 31, 2017
Numerator:
Net income	$ 204,800,000	$ 11,800,000		$ 211,900,000	$ 8,400,000
Less: Cumulative dividends on Series A Preferred Stock	(300,000)	(200,000)		(500,000)	(400,000)
Net income attributable to common stockholders	204,500,000	11,600,000		211,400,000	8,000,000
Net income attributable to common stockholders - diluted	$ 204,800,000	$ 11,800,000		$ 211,900,000	$ 8,000,000
Weighted-average number of common shares outstanding
Basic (in shares)	62.2	60.3		61.9	60.1
Effect of dilutive securities from stock-based benefit plans (in shares)	0.9	0.9		1.1	1.0
Effect of diluted securities from Series A Preferred Stock (in shares)	1.5	1.5		1.5	0.0
Diluted shares available to common stockholders (in shares)	64.6	62.7		64.5	61.1
Net income per share attributable to common stockholders:
Basic (usd per share)	$ 3.29	$ 0.19	$ 3.42	$ 3.42	$ 0.13
Diluted (usd per share)	$ 3.17	$ 0.19	$ 3.29	$ 3.29	$ 0.13
Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from calculation of diluted shares (in shares)					1.5
Convertible Debt | Convertible Senior Notes Due 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Debt, aggregate principal amount	$ 450,000,000			$ 450,000,000		$ 450,000,000	$ 450,000,000
Debt, stated interest rate							0.25%