Commitments and Contingencies - Minimum Future Rental Payments Due on Ground Leases (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Minimum Future Rental Payments Due
2019	$ 11,300
2020	15,000
2021	14,500
2022	14,300
2023	14,400
Thereafter	101,900
Total	171,400
Present value adjustment for remaining lease payments	(42,300)
Lease liability - operating leases, net	$ 129,145
Weighted average discount rate (percent)	4.28%
Weighted average remaining lease term	12 years 9 months 18 days
Ground Leases Paid by Realty Income
Minimum Future Rental Payments Due
2019	$ 1,200
2020	1,500
2021	1,300
2022	1,200
2023	1,300
Thereafter	19,800
Total	26,300
Ground Leases Paid by Our Tenants
Minimum Future Rental Payments Due
2019	10,100
2020	13,500
2021	13,200
2022	13,100
2023	13,100
Thereafter	82,100
Total	$ 145,100
Minimum
Minimum Future Rental Payments Due
Discount rate used to present value lease payments (percent)	3.09%
Maximum
Minimum Future Rental Payments Due
Discount rate used to present value lease payments (percent)	5.37%