Rental Properties Disposition (Details)		12 Months Ended
	Apr. 06, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) properties	Dec. 31, 2016
Significant Acquisitions and Disposals [Line Items]
Payments to Acquire Property, Plant, and Equipment	$ 61,200,000
number of properties sold				9
Entertainment Reportable Operating Segment [Member]
Significant Acquisitions and Disposals [Line Items]
number of properties sold		4	4
Proceeds from Sale of Property, Plant, and Equipment		$ 7,300,000	$ 72,400,000
Gain (Loss) on Disposition of Assets		$ 1,200,000	19,400,000
Education Property [Member]
Significant Acquisitions and Disposals [Line Items]
Payments to Acquire Property, Plant, and Equipment			$ 38,500,000
number of properties sold			3
number of properties sold pursuant to tenant purchase option		1	8
Education Property [Member] | Education Reportable Operating Segment [Member]
Significant Acquisitions and Disposals [Line Items]
number of properties sold | properties			2
Proceeds from Sale of Property, Plant, and Equipment			$ 10,500,000
Gain (Loss) on Disposition of Assets			1,800,000
Proceeds from sale of property, plant, and equipment tenant purchase option		$ 12,000,000	97,300,000
Gain (Loss) on disposition of assets from tenant purchase option		$ 1,900,000	$ 20,700,000
Theatre Properties Member
Significant Acquisitions and Disposals [Line Items]
Number of properties acquired		2	6
Payments to Acquire Property, Plant, and Equipment		$ 22,400,000	$ 154,100,000
Other Recreation [Member]
Significant Acquisitions and Disposals [Line Items]
Number of properties acquired			6
Payments to Acquire Property, Plant, and Equipment		$ 36,400,000	$ 62,700,000
early childhood education center [Member]
Significant Acquisitions and Disposals [Line Items]
Number of properties acquired		4
Payments to Acquire Property, Plant, and Equipment		$ 17,700,000
Proceeds from Sale of Property, Plant, and Equipment		2,500,000
Gain (Loss) on Disposition of Assets		$ 0
number of properties sold pursuant to tenant purchase option		2
Public charter school properties [Member]
Significant Acquisitions and Disposals [Line Items]
Number of properties acquired		2
Imagine Schools [Member]
Significant Acquisitions and Disposals [Line Items]
number of properties sold		4	13	7