Discontinued Operations - Narrative (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2019
May 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Shares converted   0.10
Spirit MTA REIT | Spinoff    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Cash inflows from continuing involvement subsequent to spin-off $ 22.7  
Cash outflows from continuing involvement subsequent to spin-off $ 22.7