Summary of Significant Accounting Policies Advertising Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Company Operated Restaurant Advertising Expense	$ 365.8	$ 388.8	$ 532.9
Other Marketing Related Expenses	$ 81.5	$ 88.0	$ 100.2