Acquisitions - Consideration Paid (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 277,263	$ 278,337	$ 251,024
In Bet Gaming [Member]
Business Acquisition [Line Items]
Total consideration	$ 9,600
Business Combination, Contingent Consideration, Liability	2,600
Goodwill	3,200
Intangible assets	$ 5,500
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	9 years
Gameiom Technologies Limited [Member]
Business Acquisition [Line Items]
Contractual cash purchase price adjusted for working capital		4,500
Seller note		500
Total consideration		5,000
Goodwill		3,700
Intangible assets		$ 2,100
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		6 years 8 months
Deferred Consideration To Acquire Business, Payment Terms		18 months