RESTRUCTURING (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jan. 02, 2016
Restructuring Cost and Reserve
Restructuring (income)/expense	$ 4,307	$ (598)	$ 2,997
Restructuring Reserve	0	$ 0
Employee severance
Restructuring Cost and Reserve
Restructuring (income)/expense	1,600
Equipment relocation
Restructuring Cost and Reserve
Restructuring (income)/expense	100
Asset write-off, net of gain on disposal
Restructuring Cost and Reserve
Restructuring (income)/expense	1,600
Other
Restructuring Cost and Reserve
Restructuring (income)/expense	1,000
Operating Segments | Water Systems
Restructuring Cost and Reserve
Restructuring (income)/expense	2,700
Operating Segments | Water Systems | Employee severance
Restructuring Cost and Reserve
Restructuring (income)/expense	1,600
Operating Segments | Water Systems | Equipment relocation
Restructuring Cost and Reserve
Restructuring (income)/expense	100
Operating Segments | Water Systems | Asset write-off, net of gain on disposal
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Water Systems | Other
Restructuring Cost and Reserve
Restructuring (income)/expense	1,000
Operating Segments | Fueling Systems
Restructuring Cost and Reserve
Restructuring (income)/expense	1,600
Operating Segments | Fueling Systems | Employee severance
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Fueling Systems | Equipment relocation
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Fueling Systems | Asset write-off, net of gain on disposal
Restructuring Cost and Reserve
Restructuring (income)/expense	1,600
Operating Segments | Fueling Systems | Other
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Distribution
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Distribution | Employee severance
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Distribution | Equipment relocation
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Distribution | Asset write-off, net of gain on disposal
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Operating Segments | Distribution | Other
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Intersegment Eliminations/Other | Intersegment Eliminations/Other
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Intersegment Eliminations/Other | Intersegment Eliminations/Other | Employee severance
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Intersegment Eliminations/Other | Intersegment Eliminations/Other | Equipment relocation
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Intersegment Eliminations/Other | Intersegment Eliminations/Other | Asset write-off, net of gain on disposal
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Intersegment Eliminations/Other | Intersegment Eliminations/Other | Other
Restructuring Cost and Reserve
Restructuring (income)/expense	0
Minimum
Restructuring Cost and Reserve
Restructuring and related cost, expected cost	2,000
Maximum
Restructuring Cost and Reserve
Restructuring and related cost, expected cost	$ 4,000