Nature of Business and Financial Statement Presentation - Non-cash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Other Significant Noncash Transactions [Line Items]
Dividends declared, but not paid	$ 44,047	$ 44,600	$ 44,036
Accounts payable related to construction in progress	7,700	8,800
Building [Member]
Other Significant Noncash Transactions [Line Items]
Assumption of buildings due to ground lease terminations	$ 3,000	$ 0

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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