Annual report pursuant to Section 13 and 15(d)

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)

v3.22.0.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)
 12 Months Ended
Dec. 31, 2021
USD ($)
item
shares
Dec. 31, 2020
USD ($)
item
shares
Dec. 31, 2019
USD ($)
item
shares
Dec. 31, 2018
shares
Summary of significant accounting policies        
Revenues $ 2,424,300,000 $ 2,161,220,000 $ 2,015,477,000  
Deferred revenue 168,607,000 149,224,000 136,507,000  
Retained earnings 500,919,000 $ 358,888,000    
Goodwill impairment loss 0      
Impairment of intangible assets $ 0      
Number of stock options outstanding | shares 0      
Accounting Standards Update 2016-13 [Member] | Impact of adoption of ASC        
Summary of significant accounting policies        
Retained earnings     $ 2,500,000  
Time Lapse Restricted Shares Issued 2004 [Member]        
Summary of significant accounting policies        
Award vesting period 6 years      
Annual percentage after the first year awards are vested 20.00%      
Number of potentially dilutive instruments outstanding | shares 2,596,000 2,870,000 3,465,000 4,086,000
UNITED STATES        
Summary of significant accounting policies        
Number of franchise agreements | item 135 128 134  
Revenues $ 2,240,226,000 $ 2,006,368,000 $ 1,862,698,000  
International        
Summary of significant accounting policies        
Number of franchise agreements | item 103 101 104  
Revenues $ 184,074,000 $ 154,852,000 $ 152,779,000  
Percent of total revenues 8.00% 7.00% 8.00%  
Cash held in FDIC $ 27,200,000      
Franchising revenue        
Summary of significant accounting policies        
Revenues $ 15,500,000 $ 15,200,000 $ 17,100,000  
Maximum | Franchising revenue        
Summary of significant accounting policies        
Percent of total revenues 1.00% 1.00% 1.00%  
Maximum | Equipment rental        
Summary of significant accounting policies        
Percent of total revenues 1.00% 1.00% 1.00%