Investments in and Advances to Joint Ventures - Condensed Combined Financial Information of Company's Unconsolidated Joint Venture Investments (Parenthetical) (Detail) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Schedule Of Equity Method Investments [Line Items]
Preferred investment interest valuation allowance	$ 110.9	$ 87.9
PIK [Member]
Schedule Of Equity Method Investments [Line Items]
Redeemable preferred equity, net	$ 19.5	$ 17.3

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