Goodwill and Other Intangible Assets - Goodwill and other intangible assets rollforward (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
Goodwill
Goodwill, beginning of period	$ 1,213,524
Goodwill, foreign currency translation	18,749
Goodwill, end of period	1,232,273
Intangible assets with an indefinite life
Intangible assets with an indefinite life, beginning of period	682,779
Indefinite-lived intangible assets, foreign currency translation	14,950
Intangible assets with an indefinite life, end of period	697,729
Intangible assets with a definite life
Intangible assets with a definite life, beginning of period	307,350
Amortization	(16,876)
Identified definite life intangible assets, foreign currency translation	6,538
Intangible assets with a definite life, end of period	297,012
Total
Goodwill and other intangible assets, beginning of period	2,203,653
Amortization	(16,876)
Foreign currency translation	40,237
Goodwill and other intangible assets, end of period	$ 2,227,014