Acquisitions - WEST (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended
		Oct. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Assets Acquired [Abstract]
Goodwill				$ 149.9	$ 131.2
Water & Energy Systems Technology [Member]
Business Acquisition [Line Items]
Percentage of Voting Interests Acquired		100.00%
Name of Acquired Entity		Water & Energy Systems Technology of Nevada, Inc.
Total Consideration		$ 6.7
Cash Payment to Acquire Business		5.9
Working Capital Adjustments			$ 0.2
Payment Due in April 2018		0.6
Assets Acquired [Abstract]
Cash and Cash Equivalents		0.1
Other Current Assets		1.0
Customer Relationships	[1]	2.8
Goodwill	[1],[2]	4.2
Other Non-Current Assets		0.1
Total Assets Acquired		8.2
Liabilities Assumed [Abstract]
Current Liabilities		0.3
Non-Current Liabilities		1.2
Total Liabilities Assumed		1.5
Net Identifiable Assets Acquired		6.7
Tax Deductible Goodwill		$ 0.0

[1] Presented within Goodwill and Intangible Assets – Net on the Consolidated Balance Sheet. (See Note 4. Goodwill and Intangible Assets.)

[2] For tax purposes, the purchase price allocation resulted in no allocation to goodwill.