Selected Quarterly Financial Data (unaudited) - Additional information (Details) $ in Thousands	3 Months Ended						12 Months Ended
	Dec. 31, 2018 USD ($) property	Jun. 30, 2018 USD ($) property	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($) property	Mar. 31, 2017 USD ($) property	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Quarterly Financial Information Disclosure [Abstract]
Gain on sales of real estate assets	$ 10,800	$ 27,700	$ 39,524		$ 16,100	$ 23,400	$ 41,665	$ 39,524	$ 41,044
Number of properties sold | property	3	12			3	6
Impairment charges				$ 5,100
Loss on extinguishment of debt			$ 45,000					$ 44,985