Dispositions and Assets Held for Sale - Dispositions and Assets Held for Sale (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 37,431	$ 126,386	$ 271,119	$ 381,440
Expenses:
Interest expense	455	643	1,716	2,144
Property operating expenses	22,576	79,989	172,738	233,858
Provision for depreciation	188	16,556	25,563	55,341
Total expenses	23,219	97,188	200,017	291,343
Income (loss) from real estate dispositions, net	$ 14,212	$ 29,198	$ 71,102	$ 90,097