Real Estate Intangibles (Real Estate Intangible Maturity Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2018, amortization expense	$ 32,456
2019, amortization expense	87,011
2020, amortization expense	57,221
2021, amortization expense	24,300
2022, amortization expense	19,325
Thereafter, amortization expense	152,302
Net book value	372,615	$ 377,034
Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract]
2018, amortization income	1,433
2019, amortization income	5,437
2020, amortization income	4,938
2021, amortization income	4,444
2022, amortization income	3,971
Thereafter, amortization income	17,049
Real Estate Intangible Liabilities Net	$ 37,272	$ 29,341