Property Dispositions - Narrative (Details) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 31, 2020 USD ($) Bed	May 31, 2019 USD ($) Bed	Jun. 30, 2020 USD ($) Bed	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Bed	Jun. 30, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of beds | Bed			111,900		111,900
Gain from disposition of real estate			$ 0	$ (282)	$ 48,525	$ (282)
Proceeds from disposition of properties and land parcels					146,144	8,854
Loss from disposition of real estate			0	(282)	48,525	(282)
Provision for impairment			$ 0	$ 0	$ 0	$ 3,201
The Varsity | Owned properties | Disposal Group, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of beds | Bed	901
Purchase price of property	$ 148,000
Net proceeds	146,100
Gain from disposition of real estate	$ 48,500
Wholly Owned Properties | Disposal Group, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of beds | Bed		544
Sale of property		$ 9,500
Proceeds from disposition of properties and land parcels		8,900
Loss from disposition of real estate		(300)
Provision for impairment		$ 3,200