Accounts payable and accrued expenses (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Outstanding checks in excess of cash	$ 3,093	$ 9,924
Accounts payable, trade	845,257	824,956
Accrued expenses	471,247	461,035
Product warranties	53,769	49,184
Accrued interest	17,745	21,050
Accrued compensation and benefits	227,473	192,991
Total accounts payable and accrued expenses	$ 1,618,584	$ 1,559,140