Related Party Transactions and Arrangements - Investments in SMTA (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
May 31, 2018
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Related Party Transaction [Line Items]        
Preferred stock, shares issued   6,900,000   6,900,000
Dividend rate   6.00%    
Preferred stock, liquidation preference (in USD per share)   $ 25    
Preferred dividend income from SMTA   $ 3,750 $ 0  
Preferred equity investment in SMTA   150,000   $ 150,000
Affiliated Entity        
Related Party Transaction [Line Items]        
Preferred dividend income from SMTA   3,800    
Dividends receivable   $ 3,800   $ 3,800
Spirit MTA REIT | Affiliated Entity        
Related Party Transaction [Line Items]        
Preferred stock, shares issued 6,000,000      
Aggregate liquidation preference amount $ 150,000      
Dividend rate 10.00%      
Preferred stock, liquidation preference (in USD per share) $ 25      
Liquidation value on a quarterly basis (in USD per share) 0.625      
Liquidation value on an annual basis (in USD per share) $ 2.50