Real Estate Investments and Related Intangibles - Schedule of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Acquisitions, 2020 [Member]
Real estate investments, at cost:
Land	$ 19,953
Buildings, fixtures and improvements	95,728
Total tangible assets	115,681
Acquired intangible assets:
Total purchase price of assets acquired	147,121
Acquisitions, 2020 [Member] | In-place leases and other intangible assets [Member]
Acquired intangible assets:
Acquired intangible assets	$ 15,739
Weighted-average useful life	18 years 1 month 6 days
Acquisitions, 2020 [Member] | Above-market leases [Member]
Acquired intangible assets:
Acquired intangible assets	$ 15,701
Weighted-average useful life	20 years 1 month 6 days
Acquisitions, 2019 [Member]
Real estate investments, at cost:
Land		$ 40,460
Buildings, fixtures and improvements		135,182
Total tangible assets		175,642
Acquired intangible assets:
Total purchase price of assets acquired		200,459
Acquisitions, 2019 [Member] | In-place leases and other intangible assets [Member]
Acquired intangible assets:
Acquired intangible assets		$ 24,817
Weighted-average useful life		15 years 9 months 18 days
Acquisitions, 2019 [Member] | Above-market leases [Member]
Acquired intangible assets:
Acquired intangible assets		$ 0