Real Estate Investments, Net (Real Estate Sales) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Sale, of Real Estate Investments	$ 8,790	$ (70)	$ 438
Disposed by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	62,200
Gain (Loss) on Sale, of Real Estate Investments	8,790
Disposed by sale | New York Six MOBs (1 property)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	13,600
Gain (Loss) on Sale, of Real Estate Investments	2,883
Disposed by sale | Ocean Park (1)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	3,600
Gain (Loss) on Sale, of Real Estate Investments	(152)
Disposed by sale | New York Six MOBs (5 properties)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	45,000
Gain (Loss) on Sale, of Real Estate Investments	6,059
Disposed by sale | Missouri SNF Properties (1)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	27,500
Gain (Loss) on Sale, of Real Estate Investments	(70)
Disposed by sale | Dental Arts Building - Peoria, AZ
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contract Sale Price	825
Gain (Loss) on Sale, of Real Estate Investments	$ 438