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Equity and Noncontrolling Interest - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Income (loss) attributable to noncontrolling interest, before tax	$ 9.9	$ 12.5	$ 12.5
Series D Cumulative Redeemable Preferred Stock
Class of Stock [Line Items]
Depositary shares outstanding (in shares)	3.0
Percentage of redeemable preferred stock	6.125%
Liquidation preference (in usd per share)	$ 25.00
Annual dividend on depositary shares (in usd per share)	$ 1.53125
Depository shares to cumulative redeemable preferred stock ratio	1.00%
Series E Cumulative Redeemable Preferred Stock
Class of Stock [Line Items]
Depositary shares outstanding (in shares)	4.4
Percentage of redeemable preferred stock	6.00%
Liquidation preference (in usd per share)	$ 25.00
Annual dividend on depositary shares (in usd per share)	$ 1.50
Depository shares to cumulative redeemable preferred stock ratio	1.00%

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