Goodwill And Intangible Assets (Summary Of Intangible Assets) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	17 years 10 months 24 days
Intangible Assets, Gross (Excluding Goodwill)	$ 935.8	$ 890.0
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	34.2
Finite-Lived Intangible Assets, Amortization Expense, Year Two	42.7
Finite-Lived Intangible Assets, Amortization Expense, Year Three	42.3
Intangible assets, net	545.4	505.1	$ 481.8
Finite-Lived Intangible Assets, Net	545.4
Finite-Lived Intangible Assets, Accumulated Amortization	390.4	384.9
Finite-Lived Intangible Assets, Amortization Expense, Year Four	42.1
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 314.7
Intellectual Property Rights
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years 8 months 12 days
Intangible Assets, Gross (Excluding Goodwill)	$ 135.3	134.2
Intangible assets, net	79.3	77.4
Finite-Lived Intangible Assets, Accumulated Amortization	$ 56.0	56.8
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years 4 months 24 days
Intangible Assets, Gross (Excluding Goodwill)	$ 649.1	603.1
Intangible assets, net	403.3	361.8
Finite-Lived Intangible Assets, Accumulated Amortization	$ 245.8	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	0.6	0.6
Finite-Lived Intangible Assets, Accumulated Amortization	$ 10.5	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)	$ 140.3	141.6
Intangible assets, net	62.2	65.3
Finite-Lived Intangible Assets, Accumulated Amortization	$ 78.1	$ 76.3