Subsequent Event (Details) $ in Millions	1 Months Ended	6 Months Ended
	Jul. 31, 2020 USD ($)	Jun. 30, 2020 USD ($) Rate	Jun. 30, 2019 USD ($)	Jul. 17, 2020 USD ($)
Subsequent Event [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired		$ 11.3	$ 703.7
Senior Notes Became Due During Quarter		412.2
Cash Payment Received Appropriated by U.S. Congress Covid-19		55.9
Other acquirees [Member]
Subsequent Event [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired		$ 17.3	$ 117.7
Subsequent Event [Member]
Subsequent Event [Line Items]
Notice Given to Holders of Senior Notes Due Q4 2020 Company Will Redeem August 17, 2020				$ 412.2
Subsequent Event [Member] | Other acquirees [Member]
Subsequent Event [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 200.0
Term Loan and Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Debt to EBITDA (Leverage) Ratio Quarter Ending 1 Year From Present		4.5
Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Revolving Credit Facility Accrue Interest per Annum at Libor Plus Margin Percentage | Rate		1.25%
Revolving Credit Facility Accrue Interest Per Annum Base Rate Plus Percentage | Rate		0.25%
Revolving Credit Facility Fee Percentage Required to Pay on Outstanding Commitments | Rate		0.25%
Maximum [Member] | Term Loan and Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Debt to EBITDA (Leverage) Ratio Next Three Quarters		5.0