Schedule II - Schedule of Valuation and Qualifying Accounts (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase in real estate impairment reserve		$ 21.0	$ 48.0
Increase in accounts receivable and other reserves		22.0
Increase (decrease) in valuation allowance		7.9	(7.7)	$ (4.9)
Increase (decrease) in real estate impairment reserve related to disposals		$ (7.2)
Increase in accounts receivable reserve			$ 9.3
Domestic Valuation Allowances [Member]
Increase (decrease) in valuation allowance	$ (4.4)