SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 980	$ 637	$ 623
Charged to costs and expenses	(286)	422	160
Other additions	220	(61)	2
Deductions	78	18	148
Balance at end of year	836	980	637
Balance of valuation allowance	980	637	623
Environmental Reserves [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	28,004	21,864	21,667
Charged to costs and expenses	1,981	7,491	894
Other additions	0	0	0
Deductions	6,366	1,351	697
Balance at end of year	23,619	28,004	21,864
Balance of valuation allowance	28,004	21,864	21,667
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	30,316	18,681	17,650
Charged to costs and expenses	1,209	7	3
Other additions	150	11,628	1,028
Deductions	6,364	0	0
Balance at end of year	25,311	30,316	18,681
Period increase in valuation allowance		11,600
Balance of valuation allowance	$ 30,316	$ 18,681	$ 17,650