Condensed Consolidated Balance Sheets (Parenthetical) $ in Millions	Dec. 30, 2016 € / shares	Dec. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2016 € / shares	Sep. 30, 2016 USD ($) $ / shares shares
Allowance for doubtful accounts | $		$ 4.0		$ 4.0
Preferred shares, par value (in usd per share) | $ / shares		$ 0.20		$ 0.20
Preferred shares, shares authorized (in shares)		500,000,000		500,000,000
Preferred shares, shares issued (in shares)		0		0
Preferred shares, shares outstanding (in shares)		0		0
Ordinary shares, par value (in usd per share) | $ / shares		$ 0.20		$ 0.20
Ordinary shares, shares authorized (in shares)		500,000,000		500,000,000
Ordinary shares, shares issued (in shares)		118,182,944		118,137,297
Ordinary shares, shares outstanding (in shares)		104,667,545		107,167,693
Ordinary shares held in treasury at cost (in shares)		13,515,399		10,969,604
Ordinary A
Ordinary shares | $		$ 0.0		$ 0.0
Ordinary shares, par value (in usd per share) | € / shares	€ 1.00		€ 1.00
Ordinary shares, shares authorized (in shares)		40,000		40,000
Ordinary shares, shares issued (in shares)		0		0
Ordinary A shares, shares outstanding (in shares)		0		0