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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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