Real Estate Investments - Nonmonetary Exchange Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2017 USD ($) property	Sep. 30, 2016 property
Real Estate [Line Items]
Number of real estate properties disposed	6
Red Lobster [Member]
Real Estate [Line Items]
Number of real estate properties disposed in non monetary exchange	15
Number of real estate properties disposed	24	47
Fair value of assets disposed | $	$ 50.1
Gain on acquisition and disposition of assets | $	$ 7.4
Bob Evans [Member]
Real Estate [Line Items]
Number of real estate properties acquired	22
Fair value of properties acquired | $	$ 50.1