Property Dispositions - Schedule of Property Dispositions (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) Bed	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Provision for impairment | $		$ 17,214	$ 0	$ 15,317
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 in properties sold | Bed		1,150
Provision for impairment | $				$ 4,900
College Club Townhomes | 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 in properties sold | Bed		544
Provision for impairment | $	$ 3,200
Landmark | 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 in properties sold | Bed		606