Income taxes - Provision (Benefit) for Income Taxes on Income from Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 28, 2014
Current
Federal	$ 189,900	$ 114,161	$ 139,710
State and other	13,107	12,795	23,114
Foreign	1,537	1,849	1,100
Total	204,544	128,805	163,924
Deferred
Federal	25,854	76,816	51,245
State and other	(12,077)	(2,247)	20,232
Foreign	(1,342)	(1,060)	(930)
Total	12,435	73,509	70,547
Total
Federal	215,754	190,977	190,955
State and other	1,030	10,548	43,346
Foreign	195	789	170
Total	$ 216,979	$ 202,314	$ 234,471