Schedule II - Valuation And Qualifying Accounts (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance as of Beginning of Period	$ 530.1	$ 536.0	$ 677.1
Additions	20.6	66.0	48.9
Retirements	(66.3)	(30.4)	(127.0)
Other Changes	(6.0)	(41.5)	(63.0)
Balance as of End of Period	478.4	530.1	536.0
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance as of Beginning of Period	34.4	27.5	34.5
Additions	12.0	14.1	7.6
Retirements	(12.7)	(4.5)	(10.0)
Other Changes	(0.9)	(2.7)	(4.6)
Balance as of End of Period	32.8	34.4	27.5
Allowance for deferred tax assets
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance as of Beginning of Period	495.7	508.5	642.6
Additions	8.6	51.9	41.3
Retirements	(53.6)	(25.9)	(117.0)
Other Changes	(5.1)	(38.8)	(58.4)
Balance as of End of Period	$ 445.6	$ 495.7	$ 508.5