Goodwill And Intangible Assets (Summary Of Intangible Assets) (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years
Intangible Assets, Gross (Excluding Goodwill)	$ 938.3	$ 890.0
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	22.5
Finite-Lived Intangible Assets, Amortization Expense, Year Two	42.2
Finite-Lived Intangible Assets, Amortization Expense, Year Three	41.8
Intangible assets, net	534.4	505.1	$ 481.8
Finite-Lived Intangible Assets, Accumulated Amortization	403.9	384.9
Finite-Lived Intangible Assets, Amortization Expense, Year Four	41.6
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 316.6
Intellectual Property Rights
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years 7 months 6 days
Intangible Assets, Gross (Excluding Goodwill)	$ 135.7	134.2
Intangible assets, net	79.1	77.4
Finite-Lived Intangible Assets, Accumulated Amortization	$ 56.6	56.8
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years 6 months
Intangible Assets, Gross (Excluding Goodwill)	$ 650.3	603.1
Intangible assets, net	394.4	361.8
Finite-Lived Intangible Assets, Accumulated Amortization	$ 255.9	241.3
Drawings
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	40 years
Intangible Assets, Gross (Excluding Goodwill)	$ 11.1	11.1
Intangible assets, net	0.5	0.6
Finite-Lived Intangible Assets, Accumulated Amortization	$ 10.6	10.5
Other Intangible Assets
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	11 years 8 months 12 days
Intangible Assets, Gross (Excluding Goodwill)	$ 141.2	141.6
Intangible assets, net	60.4	65.3
Finite-Lived Intangible Assets, Accumulated Amortization	$ 80.8	$ 76.3