Investment Activity - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($) mezzanine_loan land state healthcareproperty	Sep. 30, 2020 USD ($) mezzanine_loan state healthcareproperty land
Noncash or Part Noncash Acquisitions [Line Items]
Number of operating healthcare properties | healthcareproperty	1	3
Number of states in which operating healthcare properties and land parcel located | state	3	3
Asset acquisition, consideration transferred	$ 21.1	$ 33.3
Number of land parcels acquired | land	1	1
Payments for loans receivable and payments to acquire real estate	$ 67.2	$ 67.2
Outstanding loans receivable	5.5	$ 5.5
1st Quarter
Noncash or Part Noncash Acquisitions [Line Items]
Number of operating healthcare properties | healthcareproperty		2
Asset acquisition, consideration transferred		$ 1.1
Payments for loans receivable and payments to acquire real estate	$ 24.5	24.5
Term Loan
Noncash or Part Noncash Acquisitions [Line Items]
Asset acquisition, consideration transferred		47.0
Term Loan | 1st Quarter
Noncash or Part Noncash Acquisitions [Line Items]
Asset acquisition, consideration transferred		$ 0.2
Real Estate Loan
Noncash or Part Noncash Acquisitions [Line Items]
Number of mezzanine loans collateralized | mezzanine_loan	1	1
Payments for (proceeds from) loans receivable		$ 13.0
Construction Loans
Noncash or Part Noncash Acquisitions [Line Items]
Payments for (proceeds from) loans receivable		19.6
Construction Loans | 1st Quarter
Noncash or Part Noncash Acquisitions [Line Items]
Asset acquisition, consideration transferred	$ 0.6
Payments for (proceeds from) loans receivable		$ 2.8