Summary of Significant Accounting Policies - Narratives (Details) - USD ($)	3 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Significant Accounting Policies [Line Items]
Advertising expense			$ 81,500,000	$ 88,500,000	$ 158,400,000
Impairment of long-lived assets			(282,000)	(14,751,000)	(7,259,000)
Impairment of goodwill			0	0	3,097,000
Loss on sale of business, net			0	0	4,674,000
Impairment charges related to equity method investments			19,300,000	7,300,000
Foreign currency transaction gains and (losses)			400,000	(400,000)	(100,000)
Sass for Vacation Rentals
Significant Accounting Policies [Line Items]
Impairment of long-lived assets					(7,300,000)
Impairment of goodwill		$ 3,100,000
Loss on sale of business, net	$ 4,700,000
Hotel Franchising
Significant Accounting Policies [Line Items]
Impairment of goodwill			0	0	0
Impairment of intangible assets, indefinite-lived (excluding goodwill)			0	0	$ 0
Property and equipment
Significant Accounting Policies [Line Items]
Interest costs capitalized			$ 700,000	$ 100,000