Shareholders' equity (Share repurchase program textuals) (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended	3 Months Ended
	Sep. 29, 2018	Sep. 29, 2018	Sep. 30, 2017	Aug. 29, 2018
Shareholders' equity
Increase in authorized repurchase amount				$ 500,000
Authorized repurchase of common stock under Share Repurchase Program	$ 2,450,000	$ 2,450,000
Shares repurchased during period (in shares)		3.3
Cost of repurchase		$ 156,900
Remaining authorized repurchase amount	$ 615,200	$ 615,200
Cash dividends paid per common share	$ 0.20	$ 0.20	$ 0.18
Dividends paid on common stock		$ 22,932	$ 22,012