Acquisitions - 2017 Acquired Intangible Assets (Details) - USD ($) $ in Thousands	1 Months Ended
	Sep. 30, 2017	Jan. 31, 2017
Ticketfly
Business Acquisition [Line Items]
Acquired intangible assets	$ 76,300
ticketscript
Business Acquisition [Line Items]
Acquired intangible assets		$ 11,800
Customer relationships | Ticketfly
Business Acquisition [Line Items]
Acquired intangible assets	$ 60,500
Weighted-average remaining useful life	8 years
Customer relationships | ticketscript
Business Acquisition [Line Items]
Acquired intangible assets		$ 10,600
Weighted-average remaining useful life		5 years
Developed technology | Ticketfly
Business Acquisition [Line Items]
Acquired intangible assets	$ 14,500
Weighted-average remaining useful life	1 year 3 months 18 days
Developed technology | ticketscript
Business Acquisition [Line Items]
Acquired intangible assets		$ 1,100
Weighted-average remaining useful life		1 year
Trademark | Ticketfly
Business Acquisition [Line Items]
Acquired intangible assets	$ 1,300
Weighted-average remaining useful life	1 year 3 months 18 days
Trademark | ticketscript
Business Acquisition [Line Items]
Acquired intangible assets		$ 100
Weighted-average remaining useful life		1 year