Series B Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands				9 Months Ended
	Oct. 01, 2019	Mar. 29, 2019	Feb. 03, 2019	Sep. 29, 2019
Redeemable Preferred Shares
Preferred stock dividend rate				3.60%
Authorized shares of preferred stock				5,000,000.0
Temporary equity				$ 251,074
Issuance costs				7,535
Dividends paid to preferred shareholders				6,608
Preferred dividends				3,400
Common stock dividends paid to preferred shareholders				3,200
General and administrative expenses
Redeemable Preferred Shares
Temporary equity adjustment				$ 5,900
Series B Preferred Stock
Redeemable Preferred Shares
Authorized shares of preferred stock				260,000
Temporary equity				$ 251,100
Temporary equity adjustment				5,900
Dividends paid to preferred shareholders				6,600
Preferred dividends	$ 2,300			3,400
Common stock dividends paid to preferred shareholders				3,200
Series B Preferred Stock | Franchisee
Redeemable Preferred Shares
Aggregate purchase price of shares		$ 2,500
Temporary equity adjustment				300
Series B Preferred Stock | Securities Purchase Agreement
Redeemable Preferred Shares
Aggregate purchase price of shares		$ 50,000	$ 200,000
Purchase price per share			$ 1,000
Preferred stock dividend rate			3.60%
Conversion rate			$ 50.06
Initial redemption term			8 years
Exchange Cap (as a percent)			19.99%
Issuance costs				7,500
Redemption value			$ 252,500
Series B Preferred Stock | General and administrative expenses
Redeemable Preferred Shares
Aggregate purchase price of shares				50,000
Series B Preferred Stock | General and administrative expenses | Securities Purchase Agreement
Redeemable Preferred Shares
Temporary equity adjustment				$ 5,600