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Summary of Significant Accounting Policies (Additional Information 2) (Details)
$ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
segment
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Summary Of Significant Accounting Policies [Line Items]      
Number of operating segments | segment 1    
Number of reportable segments | segment 1    
Unrecognized Tax Benefits | $ $ 0.0 $ 0.0 $ 0.0
Interest and penalties related to income taxes | $ $ 0.0 $ 0.0 $ 0.0
Lease, Practical Expedients, Package [true/false] true    
Lease, Practical Expedient, Use of Hindsight [true/false] false    
Minimum Quarterly Distribution Of Available Cash 100.00%    
Customer One | Rental Revenue      
Summary Of Significant Accounting Policies [Line Items]      
Percentage of total revenue 14.00%    
No Other Customers | Accounts Receivable | Minimum      
Summary Of Significant Accounting Policies [Line Items]      
Percentage of trade accounts receivable 10.00%    
Five Customers | Accounts Receivable      
Summary Of Significant Accounting Policies [Line Items]      
Percentage of trade accounts receivable 30.00%    
Five Customers | Accounts Receivable | Minimum      
Summary Of Significant Accounting Policies [Line Items]      
Percentage of trade accounts receivable 5.00%