Earnings Per Share (Narrative) (Details) - shares	3 Months Ended			6 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Jul. 02, 2016	Mar. 31, 2018	Apr. 01, 2017
Class of Stock [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	482,000	629,000		489,000	649,000
Equity Component
Class of Stock [Line Items]
Threshold consecutive trading days			20 days	20 days
Equity Component | Minimum | Common Class A
Class of Stock [Line Items]
Convertible, number of equity instruments per contract (in shares)			1.9841	1.9841
Equity Component | Maximum | Common Class A
Class of Stock [Line Items]
Convertible, number of equity instruments per contract (in shares)			2.3810	2.3810