Investments - Schedule of Information about Acquisition Activity (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) Property		Mar. 31, 2018 USD ($) Property
Investments [Abstract]
Ownership type	Fee Interest		Fee Interest
Number of properties acquired | Property	51		28
Allocation of Purchase Price:
Land and improvements	$ 36,375		$ 18,754
Building and improvements	79,291		38,105
Construction in progress	1,135	[1]	4,533	[2]
Leasehold improvement			28
Intangible lease assets	3,818		2,679
Assets acquired	120,620		64,099
Intangible lease liabilities	(117)		(495)
Liabilities assumed	(117)		(495)
Purchase price (including acquisition costs)	$ 120,503		$ 63,604

[1] Represents amounts incurred at and subsequent to acquisition and includes approximately $25,000 of capitalized interest expense.

[2] Represents amounts incurred at and subsequent to acquisition and includes $0.1 million of capitalized interest expense