Summary of Significant Accounting Policies - Amortization of Deferred Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of Deferred Charges	$ 8,372	$ 6,235	$ 23,523	$ 17,180
Lease intangibles (in-place)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of Deferred Charges	4,408	2,854	11,971	7,298
Lease intangibles (above-market)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of Deferred Charges	5,338	4,562	15,607	13,297
Lease intangibles (below-market)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of Below Market Lease	$ (1,374)	$ (1,181)	$ (4,055)	$ (3,415)