Annual report pursuant to Section 13 and 15(d)

Introduction and Basis of Presentation - Narrative (Details)

v3.19.3.a.u2
Introduction and Basis of Presentation - Narrative (Details)
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Pinedale LP      
Schedule of Equity Method Investments [Line Items]      
Equity interest percentage 100.00% 100.00%  
Grand Isle Corridor LP      
Schedule of Equity Method Investments [Line Items]      
Equity interest percentage 100.00% 100.00% 100.00%