Stock-Based Compensation and Other Stock Plans - Other Stock Plans Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Directors' Fee Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Percentage of non-employee directors fee	100.00%
Number of shares issued (in shares)	1,784	1,727	1,800
Deferred shares received (in shares)	1,374	1,315	1,312
Number of shares reserved for issuance (in shares)	184,146
Non-employee Directors \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Shares granted (in shares)	7,605	6,975	6,966
Vesting period	1 year
Employees Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Number of shares issued (in shares)	25,820	22,794	26,963
Number of shares reserved for issuance (in shares)	704,986
Employee contributions for purchase of common stock	$ 2.2
Stock based compensation expense (benefit)	$ 0.1	$ 0.3	$ 0.1
Franchisee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Number of shares issued (in shares)	49,921	46,704	47,314
Number of shares reserved for issuance (in shares)	469,530
Stock based compensation expense (benefit)	$ 0.8	$ 0.6	$ 0.2
Franchisee contributions for purchase of common stock	$ 4.9

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Employee Contributions For Purchase Of Common Stock

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Percentage Of Non-Employee Directors Fee

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