Goodwill - Changes In Carrying Amount of Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 343,900,000	$ 345,300,000
Purchase price adjustment related to business acquisition		(1,500,000)
Impairment loss	(92,200,000)
Goodwill, ending balance	251,628,000	343,900,000
Applebee's | Franchised
Goodwill [Roll Forward]
Goodwill, beginning balance	328,400,000	328,400,000
Purchase price adjustment related to business acquisition		0
Impairment loss	(92,200,000)
Goodwill, ending balance	236,200,000	328,400,000
Applebee's | Entity Operated Units
Goodwill [Roll Forward]
Goodwill, beginning balance	4,600,000	6,100,000
Purchase price adjustment related to business acquisition		(1,500,000)
Impairment loss	0
Goodwill, ending balance	4,600,000	4,600,000
IHOP | Franchised
Goodwill [Roll Forward]
Goodwill, beginning balance	10,800,000	10,800,000
Purchase price adjustment related to business acquisition		0
Impairment loss	0
Goodwill, ending balance	$ 10,800,000	$ 10,800,000