Business Acquisitions - Summary of Preliminary Estimate of the Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions		6 Months Ended
	Feb. 02, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 1,759.7		$ 1,089.0
Total Estimate of Consideration Transferred, Net of Cash Acquired		$ 1,116.0	$ 108.5
Aclara
Business Acquisition [Line Items]
Accounts receivable	$ 116.4
Inventories	77.1
Other current assets	11.0
Property, plant and equipment	32.2
Intangible assets	444.0
Accounts payable	(51.8)
Other accrued liabilities	(71.6)
Deferred tax liabilities	(80.0)
Other non-current liabilities	(37.5)
Noncontrolling interest	(2.5)
Goodwill	679.0
Total Estimate of Consideration Transferred, Net of Cash Acquired	$ 1,116.3