Segment Results Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting [Abstract]
Number of Reportable Segments	3	3	3	3
Segment Reporting Information [Line Items]
Unusual or Infrequent Item, or Both, Insurance Proceeds	$ 8.0		$ 8.0
Earnings per common share - Basic	$ 0.36	$ 0.52	$ 0.78	$ 0.79
Earnings per common share - Diluted	$ 0.36	$ 0.52	$ 0.76	$ 0.78
Revenue [Member] \| Threshold for Reporting Customer Concentration [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%	10.00%
Gross Profit [Member]
Segment Reporting Information [Line Items]
Unusual or Infrequent Item, or Both, Insurance Proceeds	$ 8.0		$ 8.0
Water Operating Segment [Member] \| Insurance Recovery, net of tax [Member]
Segment Reporting Information [Line Items]
Earnings per common share - Basic	$ 0.13		$ 0.13
Earnings per common share - Diluted	$ 0.12		$ 0.13

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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