Segment Reporting - Allocated Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Cost of sales	$ 266,746	$ 244,459
Gross profit	359,590	331,597
Sales and marketing	116,143	106,584
Operating Expenses:
General and administrative	65,812	60,361
Research and development	33,310	31,514
Income from operations	144,325	133,138
Operating Segments | CAG
Operating Expenses:
Income from operations	118,659	111,719
Operating Segments | Water
Operating Expenses:
Income from operations	15,882	13,815
Operating Segments | LPD
Operating Expenses:
Income from operations	9,663	6,289
Operating Segments | Other
Operating Expenses:
Income from operations	$ 121	1,315
Restatement Adjustment | Operating Segments | CAG
Segment Reporting Information [Line Items]
Cost of sales		(182)
Gross profit		182
Sales and marketing		129
Operating Expenses:
General and administrative		(202)
Research and development		3,558
Total operating expenses		3,485
Income from operations		(3,303)
Restatement Adjustment | Operating Segments | Water
Segment Reporting Information [Line Items]
Cost of sales		(8)
Gross profit		8
Sales and marketing		6
Operating Expenses:
General and administrative		(40)
Research and development		9
Total operating expenses		(25)
Income from operations		33
Restatement Adjustment | Operating Segments | LPD
Segment Reporting Information [Line Items]
Cost of sales		(10)
Gross profit		10
Sales and marketing		7
Operating Expenses:
General and administrative		(47)
Research and development		11
Total operating expenses		(29)
Income from operations		39
Restatement Adjustment | Operating Segments | Other
Segment Reporting Information [Line Items]
Cost of sales		(4)
Gross profit		4
Sales and marketing		0
Operating Expenses:
General and administrative		215
Research and development		0
Total operating expenses		215
Income from operations		(211)
Previously Reported | Unallocated
Segment Reporting Information [Line Items]
Cost of sales		204
Gross profit		(204)
Sales and marketing		(142)
Operating Expenses:
General and administrative		74
Research and development		(3,578)
Total operating expenses		(3,646)
Income from operations		$ 3,442