Real Estate Investments, Net (Held for Sale) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 70,839	$ 52,397
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Buildings, fixtures and improvements	66,788	47,112
Land	4,051	5,285
Assets held for sale	70,839	$ 52,397
Medical Office Buildings | Market Lease Liabilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts payable and accrued expenses	3,500
Medical Office Buildings | Accounts Payable and Accrued Liabilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts payable and accrued expenses	$ 500