Other Expenses - Schedule of General and Administrative Expenses (Parenthetical) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Multifamily [Member] | Joint Venture [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Expenses related Multifamily Joint Venture.	$ 1,100,000	$ 865,000	$ 427,000