Shareholders' Equity - Additional Information (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jul. 12, 2019	Feb. 14, 2018	Nov. 09, 2017
Class of Stock [Line Items]
Minimum % of REIT taxable income to be paid as dividend annually	90.00%
Prospectus Supplement
Class of Stock [Line Items]
Maximum common stock value authorized under prospectus supplement					$ 150,000,000
Shares sold (in shares)	0	0
Amended Credit Agreement
Class of Stock [Line Items]
Maximum borrowing capacity	$ 100,000.0
Line of Credit | Revolving Credit Facility | Amended Credit Agreement
Class of Stock [Line Items]
Maximum borrowing capacity			$ 900,000,000.0	$ 900,000,000.0
Common shares | February 2018 Stock Buyback Program
Class of Stock [Line Items]
Stock repurchase program, authorized amount				$ 200,000,000.0
Purchase of treasury shares (in shares)	553,665