Real Estate Properties Real Estate Properties - SMTA Transaction and Other Acquisition Agreements (Details) $ in Thousands			12 Months Ended
	Feb. 20, 2020 USD ($) ft² retail_property state	Sep. 20, 2019 USD ($) ft² tenant retail_property state brand industry	Dec. 31, 2019 USD ($) tenant state brand industry	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Real Estate Properties [Line Items]
Number of properties acquired | retail_property		767
Rentable square feet | ft²		12,400,000
Number of states in which property is located | state		45	12
Transaction value		$ 2,482,382	$ 2,711,985	$ 127,597	$ 606,397
Cash consideration		2,384,577
Prepayment penalties		82,069
Acquisition costs capitalized		$ 15,736
Number of tenants | tenant		279	194
Number of industries | industry		23	23
Number of brands | brand		163	131
Unspent leasing related obligations assumed			$ 5,346
Annual minimum returns and rents			$ 381,679
Subsequent event
Real Estate Properties [Line Items]
Number of properties acquired | retail_property	3
Rentable square feet | ft²	6,696
Number of states in which property is located | state	2
Transaction value	$ 7,000
Annual minimum returns and rents	$ 387