Non-Controlling Interests, Common Shares and Common Shares in Treasury and Preferred Shares - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Equity [Line Items]
Operating partnership units outstanding	140,633	140,633
Common shares, issued		13,225,000
Net proceeds from issuance of common shares	$ 0	$ 194,598	$ 0
Common shares, par value	$ 0.10	$ 0.10
Stock repurchase program authorized amount			100,000
Shares repurchased	800,000	1,200,000
Shares repurchased at cost	$ 7,500	$ 14,069	$ 36,341
Class A Depositary Share [Member]
Schedule Of Equity [Line Items]
Redemption date restrictions for depositary shares	Jun. 05, 2022
Class K Depositary Share [Member]
Schedule Of Equity [Line Items]
Cumulative redeemable preferred shares, liquidation value	$ 500
Class A Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Cumulative redeemable preferred shares, liquidation value	$ 500	$ 500
Preferred Shares, without par value	750,000	750,000
Class B Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class C Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class D Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class E Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class F Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class G Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class H Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class I Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class J Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Class K Cumulative Redeemable Preferred Shares [Member]
Schedule Of Equity [Line Items]
Cumulative redeemable preferred shares, liquidation value	$ 500	$ 500
Preferred Shares, without par value	750,000	750,000
Non-Cumulative Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	750,000
Cumulative Voting Preferred Shares [Member]
Schedule Of Equity [Line Items]
Preferred Shares, without par value	2,000,000