Real Estate Investments - Impairment of Real Estate Investments Narrative (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) restaurant
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges	$ 30,857	$ 176,200
Tenant file for bankruptcy, number of restaurants | restaurant		59
Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of real estate assets deemed to be impaired	87,900	$ 655,100
Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of real estate assets deemed to be impaired	$ 57,000	$ 478,900
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Period for determining disposal is more likely than not	12 months
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Period for determining disposal is more likely than not	24 months