Stock-Based Compensation and Other Stock Plans - Other Stock Plans Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
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)	1,727	1,800	2,579
Deferred shares received (in shares)	1,315	1,312	2,019
Number of shares reserved for issuance (in shares)	176,724
Non-employee Directors \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Shares granted (in shares)	6,975	6,966	7,145
Employees Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Number of shares issued (in shares)	22,794	26,963	27,156
Number of shares reserved for issuance (in shares)	730,806
Employee contributions for purchase of common stock	$ 2.8
Stock based compensation expense (benefit)	$ 0.3	$ 0.1	$ 0.0
Franchisee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Number of shares issued (in shares)	46,704	47,314	42,867
Number of shares reserved for issuance (in shares)	519,451
Stock based compensation expense (benefit)	$ 0.6	$ 0.2	$ (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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Number of new stock issued during the period.

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