Annual report pursuant to Section 13 and 15(d)

Debt - Term Loan Facility (Narrative) (Details)

v3.20.4
Debt - Term Loan Facility (Narrative) (Details) - USD ($)
3 Months Ended 12 Months Ended
May 18, 2020
Feb. 14, 2020
Feb. 13, 2020
Jun. 25, 2020
Dec. 31, 2020
Dec. 26, 2019
Dec. 27, 2018
Debt Instrument [Line Items]              
Principle amount   $ 144,600,000     $ 217,804,000 $ 145,500,000  
Proceeds from term loan facility         75,000,000 0 $ 0
Fees to creditors         6,882,000 0 170,000
Gain (loss) on extinguishment of debt         1,015,000 0 $ 0
Term Loan Facility Accordion Feature              
Debt Instrument [Line Items]              
Borrowing capacity   $ 270,000,000.0          
Borrowing capacity as a percentage of EBITDA   100.00%          
Amended Term Loan Facility              
Debt Instrument [Line Items]              
Principle amount         $ 143,179,000 145,500,000  
Consolidated First Lien Leverage Ratio   2.50          
Consolidated Secured Leverage Ratio   3.50          
Consolidated Total Leverage Ratio   3.50          
Applicable interest rate (as a percent)         2.15%    
Amended Term Loan Facility | Maximum              
Debt Instrument [Line Items]              
Consolidated Total Leverage Ratio   4.50          
Amended Term Loan Facility | Base Rate              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent) 3.00% 1.00%          
Leverage based step-up (as a percent)   1.25%          
Amended Term Loan Facility | Base Rate | Maximum              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent)     1.75%        
Amended Term Loan Facility | Base Rate | Minimum              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent)     1.50%        
Amended Term Loan Facility | Eurodollar              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent) 4.00% 2.00%          
Leverage based step-up (as a percent)   2.25%          
Interest rate floor (as a percent) 1.00% 0.00%          
Amended Term Loan Facility | Eurodollar | Maximum              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent)     2.75%        
Amended Term Loan Facility | Eurodollar | Minimum              
Debt Instrument [Line Items]              
Basis spread on variable rate (as a percent)     2.50%        
UBS Facility Term Loan B-1              
Debt Instrument [Line Items]              
Principle amount         $ 74,625,000 $ 0  
Applicable interest rate (as a percent)         5.00%    
Fourth Amendment to Term Loan Facility              
Debt Instrument [Line Items]              
Face amount of debt $ 75,000,000.0            
Proceeds from term loan facility 70,500,000            
Original issue discount 4,100,000            
Fees to creditors $ 300,000            
Gain (loss) on extinguishment of debt       $ 1,000,000.0      
Unamortized debt issuance costs       $ 500,000