Transaction Related Costs, Impairment Losses and Other - Schedule of Transaction Related Costs, Impairment Losses and Other (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Transaction Related Costs, Impairment Losses and Other [Line Items]
Transaction related costs	$ 1,576	$ 2,510	$ 1,955	$ 3,580
Non-cash impairment loss	0	0	101,360	0
Transfer tax	0	0	0	13,103
Transaction related costs, impairment losses and other	$ 1,576	$ 2,510	$ 103,315	$ 16,683
Independence Plaza
Transaction Related Costs, Impairment Losses and Other [Line Items]
Equity method ownership percentage	50.10%		50.10%