Summary of Significant Accounting Policies Significant Accounting Policies (Details)	3 Months Ended
Mar. 31, 2019
Minimum [Member]
Ground Lease Agreement Term	five years
Maximum [Member]
Ground Lease Agreement Term	10 years

This disclosure represents the term of the Company’s ground lease agreements

No definition available.

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Data Type:	us-types:durationStringItemType
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Period Type:	duration