Shareholders' equity (Share repurchase program textuals) (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Dec. 31, 2016	Nov. 26, 2016	Dec. 31, 2016	Jan. 02, 2016	Dec. 31, 2016	Jan. 02, 2016
Shareholders' equity
Authorized repurchase of common stock under Share Repurchase Program	$ 1,250,000		$ 1,250,000		$ 1,250,000
Aggregate number of shares repurchased since inception (in shares)	31.4		31.4		31.4
Aggregate cost of shares repurchased since inception	$ 1,080,000		$ 1,080,000		$ 1,080,000
Remaining authorized repurchase amount	174,900		$ 174,900		$ 174,900
Cash dividends paid per common share		$ 0.17	$ 0.17	$ 0.17	$ 0.34	$ 0.34
Dividends paid on common stock	$ 21,800				$ 43,426	$ 45,020