Nature of Business and Financial Statement Presentation - Non-cash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Other Significant Noncash Transactions [Line Items]
Dividends declared, but not paid	$ 28,251	$ 5,100	$ 14,844
Mortgages assumed, shopping center acquisition	17,900	0
Write-off of preferred share original issuance costs	5,100	0
Accounts payable related to construction in progress	10,200	5,100
Tax receivable	4,100	0
Building [Member]
Other Significant Noncash Transactions [Line Items]
Assumption of buildings due to ground lease terminations	$ 0	$ 3,000