SEGMENT AND GEOGRAPHIC INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Segment Reporting Information
Net sales	$ 308,281	$ 355,340	$ 575,035	$ 646,055
Operating income/(loss)	33,933	43,691	47,754	55,812
Total assets	1,151,332		1,151,332		$ 1,194,743
Corporate And Eliminations
Segment Reporting Information
Net sales	(18,200)	(14,800)	(31,200)	(26,000)
Operating income/(loss)	(15,100)	(13,400)	(29,900)	(28,500)
Total assets	58,500		58,500		72,400
Water Systems | Operating Segments
Segment Reporting Information
Net sales	178,400	205,000	342,500	393,400
Operating income/(loss)	28,700	30,900	47,500	50,100
Total assets	625,200		625,200		658,300
Water Systems | United States & Canada
Segment Reporting Information
Net sales	80,800	103,100	151,700	189,900
Water Systems | United States & Canada | Intersegment Sales
Segment Reporting Information
Net sales	18,200	14,800	31,200	26,000
Water Systems | Latin America
Segment Reporting Information
Net sales	24,200	29,400	52,400	59,900
Water Systems | EMEA
Segment Reporting Information
Net sales	35,500	39,000	73,700	76,700
Water Systems | Asia Pacific
Segment Reporting Information
Net sales	19,700	18,700	33,500	40,900
Distribution | Operating Segments
Segment Reporting Information
Net sales	92,100	87,100	152,500	140,400
Operating income/(loss)	6,800	4,500	4,600	200
Total assets	200,300		200,300		180,200
Distribution | United States & Canada
Segment Reporting Information
Net sales	92,100	87,100	152,500	140,400
Distribution | United States & Canada | Intersegment Sales
Segment Reporting Information
Net sales	0	0	0	0
Fueling Systems | Operating Segments
Segment Reporting Information
Net sales	56,000	78,000	111,200	138,300
Operating income/(loss)	13,500	21,700	25,600	34,000
Total assets	267,300		267,300		$ 283,800
Fueling Systems | Intersegment Sales
Segment Reporting Information
Net sales	0	0	0	0
Fueling Systems | United States & Canada
Segment Reporting Information
Net sales	35,300	45,900	72,600	81,100
Fueling Systems | All Other
Segment Reporting Information
Net sales	$ 20,700	$ 32,100	$ 38,600	$ 57,200