Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2016	Dec. 31, 2015
Non-cash Activities [Abstract]
Fair value of assets of acquired businesses	$ 9,790.1	$ 6,969.7
Cash paid for acquired businesses	(7,224.4)	(5,599.2)
Fair value of equity awards exchanged	(6.1)
Liabilities assumed of acquired businesses	2,559.6	1,370.5
Declared but unpaid dividends	60.9	60.2
Issuance of stock upon vesting of restricted stock units	119.6	125.2
Cash and Cash Equivalents	741.1		$ 786.2
Restricted Cash Included in Other Current Assets	14.6		18.0
Restricted Cash Included in Other Assets	2.4		6.6
Cash, Cash Equivalents and Restricted Cash	$ 758.1	$ 2,000.2	$ 810.8	$ 466.3
Restricted Cash and Cash Equivalents, Current, Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsCurrent
Restricted Cash and Cash Equivalents, Noncurrent, Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsNoncurrent