Business Acquisitions - Narrative (Details) - USD ($)		1 Months Ended	3 Months Ended
	Feb. 02, 2018	Feb. 28, 2018	Mar. 31, 2018	Jan. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill			$ 1,760,100,000		$ 1,089,000,000
Line of Credit | Term Loan Agreement
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity	$ 500,000,000			$ 500,000,000
Senior Notes | Notes 2028 Term
Business Acquisition [Line Items]
Interest rate, stated percentage	3.50%	3.50%	3.50%
Face amount	$ 450,000,000	$ 450,000,000
Aclara
Business Acquisition [Line Items]
Consideration transferred to acquire business	1,100,000,000	$ 1,100,000,000
Goodwill	$ 669,000,000
Net sales			$ 90,400,000
Operating loss of acquiree since acquisition			$ 4,900,000