Basis of Presentation and Consolidation - Additional Information (Details) $ in Millions |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
|
Mar. 31, 2019
USD ($)
Restaurant
|
Mar. 31, 2018
USD ($)
|
Dec. 31, 2018
Restaurant
|
|
| Summary Of Accounting Policies [Line Items] | |||
| Equity method investment ownership percentage | 50.00% | ||
| Tenant inducements paid to franchisees | $ | $ 0 | $ 2 | |
| Restaurant VIEs | |||
| Summary Of Accounting Policies [Line Items] | |||
| Number of consolidated restaurants | Restaurant | 18 | 17 | |