Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans - Schedule of Multi-Employer Pension Plans Affecting Period-to-Period Comparability of Contributions (Details)

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Employee Benefit Plans - Schedule of Multi-Employer Pension Plans Affecting Period-to-Period Comparability of Contributions (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Retirement Benefits [Abstract]      
Pension Fund AI Pension Plan    
Entity Tax Identification Number 56-2010790    
Pension Protection Act Zone Status Red Red  
Sonic Contributions $ 181 $ 176 $ 171
Surcharge Imposed Yes    
Collective-Bargaining Agreement Expiration Date BetweenOctober 2021and February 2022