Summary of Significant Accounting Policies - Segment Information to Taxes and Accounting Pronouncements (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) subsidiary	Mar. 31, 2019	Sep. 30, 2020 USD ($) customer subsidiary segment	Sep. 30, 2019
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments | segment			1
Number of reportable segments | segment			1
Number of subsidiaries taxed as taxable REIT subsidiaries. | subsidiary	2		2
Number of taxable REIT subsidiaries in a net deferred tax liability position | subsidiary	1		1
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201602Member	us-gaap:AccountingStandardsUpdate201815Member
Cumulative Effect, Period of Adoption, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Amortization expense | $	$ 0.1		$ 0.1
Customer One | Rental Revenue
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			11.30%
Number of customers | customer			1
Customer One | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			10.80%
Number of customers | customer			1
Three Customers | Accounts Receivable | Trade Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			23.00%
Three Customers | Accounts Receivable | Minimum | Trade Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			5.00%
Taxable REIT Subsidiaries
Summary Of Significant Accounting Policies [Line Items]
Effective tax rate			(5.70%)	(8.50%)