Goodwill and Other Intangible Assets - Goodwill and other intangible assets rollforward (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill
Goodwill, beginning of period	$ 1,213,524
Goodwill, foreign currency translation	12,515
Goodwill, end of period	1,226,039
Intangible assets with an indefinite life
Intangible assets with an indefinite life, beginning of period	682,779
Indefinite-lived intangible assets, foreign currency translation	9,792
Intangible assets with an indefinite life, end of period	692,571
Intangible assets with a definite life
Intangible assets with a definite life, beginning of period	307,350
Amortization	(10,990)
Identified definite life intangible assets, foreign currency translation	4,420
Intangible assets with a definite life, end of period	300,780
Total
Goodwill and other intangible assets, beginning of period	2,203,653
Amortization	(10,990)
Foreign currency translation	26,727
Goodwill and other intangible assets, end of period	$ 2,219,390