Segment Reporting (Summary Of Restated Segment Gross Profit From Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ 83,825	$ 88,459	$ 104,162	$ 73,793	$ 66,911	$ 71,895	$ 88,303	$ 72,803	$ 350,239	$ 299,912	$ 260,255
As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 299,912	$ 260,255
Percent of Revenue										18.70%	17.50%
As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 299,912	$ 260,255
Percent of Revenue										18.70%	17.50%
CAG Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)									301,342	$ 233,319	$ 200,534
CAG Segment [Member] | As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 231,642	$ 203,536
Percent of Revenue										17.10%	16.60%
CAG Segment [Member] | Net Impact Of Standard Cost Variance Capitalization And Subsequent Recognition To The Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 1,677	$ (3,002)
CAG Segment [Member] | As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 233,319	$ 200,534
Percent of Revenue										17.20%	16.40%
Water Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)									45,702	$ 44,752	$ 38,914
Water Segment [Member] | As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 44,584	$ 39,262
Percent of Revenue										46.00%	41.40%
Water Segment [Member] | Net Impact Of Standard Cost Variance Capitalization And Subsequent Recognition To The Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 168	$ (348)
Water Segment [Member] | As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 44,752	$ 38,914
Percent of Revenue										46.20%	41.10%
LPD Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)									18,914	$ 27,157	$ 29,327
LPD Segment [Member] | As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 24,397	$ 33,788
Percent of Revenue										19.20%	23.90%
LPD Segment [Member] | Net Impact Of Standard Cost Variance Capitalization And Subsequent Recognition To The Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 2,760	$ (4,461)
LPD Segment [Member] | As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 27,157	$ 29,327
Percent of Revenue										21.40%	20.80%
Other Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)									884	$ (137)	$ 2,657
Other Segment [Member] | As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ 156	$ 2,479
Percent of Revenue										0.70%	9.20%
Other Segment [Member] | Net Impact Of Standard Cost Variance Capitalization And Subsequent Recognition To The Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ (293)	$ 178
Other Segment [Member] | As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ (137)	$ 2,657
Percent of Revenue										(0.60%)	9.90%
Unallocated Amounts [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)									$ (16,603)	$ (5,179)	$ (11,177)
Unallocated Amounts [Member] | As Previously Reported [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										(867)	(18,810)
Unallocated Amounts [Member] | Net Impact Of Standard Cost Variance Capitalization And Subsequent Recognition To The Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										(4,312)	7,633
Unallocated Amounts [Member] | As Adjusted [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)										$ (5,179)	$ (11,177)