Accounts payable and accrued expenses (Components of accounts payable and accrued expenses) (Details) - USD ($) $ in Thousands	Oct. 03, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Outstanding checks in excess of cash	$ 17,787	$ 16,083
Accounts payable, trade	771,006	622,360
Accrued expenses	347,504	269,668
Product warranties	37,762	29,350
Accrued interest	12,659	28,365
Accrued compensation and benefits	185,251	138,683
Total accounts payable and accrued expenses	$ 1,371,969	$ 1,104,509