Summary of Significant Accounting Policies (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Document Period End Date			Jun. 30, 2019
Operating Segments
Number of Reportable Operating Segments | segment			4
Revenue Recognition [Abstract]
Straight Line Rent			$ 5,600	$ 3,900
Straight line rent write off			1,400	0
Percentage rents			5,500	3,000
Mortgage And Other Participating Interest Income			0	0
Concentrations of Risk [Abstract]
Rental revenue	$ 157,330	$ 137,019	308,053	269,943
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation			$ 6,563	7,608
Share based compensation, future vesting period minimum (in years)			4 years
Range of settlement date for shares for non-employee trustee from grant date, minimum (in years)			1 year
Share based compensation expense related to employees and trustees			$ 21
Deferred Costs	32,000		32,000		$ 33,900
Accounts Receivable, Allowance for Credit Loss, Writeoff			300
Prepaymentfee			900	47,300
Recovery of Direct Costs			$ 7,700	7,700
American Multi-Cinema, Inc. [Member]
Concentrations of Risk [Abstract]
Percent of megaplex theatre rental leased by AMC			30.00%
Rental revenue			$ 61,400	$ 57,400
Percentage of lease revenue in total revenue			18.00%	16.00%
TopGolf [Member]
Concentrations of Risk [Abstract]
Percent of megaplex theatre rental leased by AMC			42.00%
Rental revenue			$ 37,700	$ 30,400
Percentage of lease revenue in total revenue			11.10%	8.50%
Minimum [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation, future vesting period minimum (in years)			3 years
Maximum [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation, future vesting period minimum (in years)			4 years
Building [Member] | Minimum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			30 years
Building [Member] | Maximum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			40 years
Furniture, fixtures & equipment [Member] | Minimum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			3 years
Furniture, fixtures & equipment [Member] | Maximum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			25 years
Building Improvements [Member] | Minimum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			10 years
Building Improvements [Member] | Maximum [Member]
Rental Properties [Abstract]
Estimated useful live of buildings (in years)			20 years
Share Options [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation, future vesting period minimum (in years)			4 years
Stock-option expense			$ 5	$ 147
Restricted Stock [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation expense related to employees and trustees			$ 5,600	6,900
Restricted Stock [Member] | Minimum [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation, future vesting period minimum (in years)			3 years
Restricted Stock [Member] | Maximum [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation, future vesting period minimum (in years)			4 years
Restricted Share Units [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Range of settlement date for shares for non-employee trustee from grant date, minimum (in years)			1 year
Restricted Share Units [Member] | Non-Employee Trustees [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share based compensation expense related to employees and trustees			$ 851	$ 570
Revolving Credit Facility [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Deferred Costs	$ 4,300		4,300		$ 5,000
triple-net lessor costs [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Recovery of Direct Costs			$ 4,300