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Summary of Significant Accounting Policies - Basis of Presentation and Real Estate Properties (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2017 property	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Basis of Presentation
Ownership interest in subsidiaries (as a percent)		100.00%
Number of properties included in joint venture agreement | property	1
Variable interest entity, consolidated, carrying amount of assets		$ 1,015,661	$ 1,061,593
Variable interest entity, consolidated, carrying amount of liabilities		704,344	714,226
Increase in capitalized above and below market leases rental income		6,791	5,787	$ 5,349
Amortization of acquired real estate leases and other intangible assets		$ 64,203	$ 72,925	$ 72,035
Above market lease, weighted average amortization period, lease term		4 years 1 month 6 days
Lease, weighted average amortization period, lease term		8 years 2 months 12 days
Below market lease, weighted average amortization period, lease term		8 years 10 months 24 days
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2020		$ 41,458
2021		37,152
2022		33,307
2023		32,226
2024		27,168
Thereafter		$ 89,859
Land and Building | Real Estate Investment | Maximum
Basis of Presentation
Estimated useful lives (up to)		40 years

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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