Earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Dec. 29, 2018	Sep. 29, 2018	Dec. 28, 2019	Dec. 29, 2018
Numerator:
Income from continuing operations	$ 5,216		$ 36,775		$ 46,968	$ 120,304
Loss from discontinued operations, net of tax	(1,548)		(374)		(1,548)	(179)
Net income	$ 3,668	$ 41,752	$ 36,401	$ 83,724	$ 45,420	$ 120,125
Denominator:
Weighted average common shares for basic earnings per share	100,431		110,332		101,781	112,796
Net effect of dilutive stock based compensation awards	871		1,130		1,058	1,171
Weighted average common shares for diluted earnings per share	101,302		111,462		102,839	113,967
Basic earnings per share - continuing operations	$ 0.05		$ 0.33		$ 0.46	$ 1.07
Basic loss per share-discontinued operations	(0.01)		0.00		(0.01)	(0.01)
Basic earnings per share	0.04		0.33		0.45	1.06
Diluted earnings per share - continuing operations	0.05		0.33		0.45	1.06
Diluted loss per share-discontinued operations	(0.01)		0.00		(0.01)	(0.01)
Diluted earnings per share	$ 0.04		$ 0.33		$ 0.44	$ 1.05
Stock Options
Denominator:
antidilutive Securities	581		1,404		500	1,205