Acquisitions and Other Investments (Details) - USD ($) $ in Thousands	Jun. 23, 2017	Jul. 27, 2017	Jun. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill			$ 8,156,716	$ 7,942,023
Subsequent Events [Abstract]
Cost investment			$ 323,000	$ 323,000
Rail Technology Distributor
Business Acquisition [Line Items]
Total consideration	$ 148,000
Cash consideration	138,000
Net assets acquired	15,000
Redeemable non-controlling interest recognized	8,000
Goodwill	100,000
Definite-lived intangible assets acquired	$ 47,000
Weighted average life of definite-lived intangibles acquired	5 years 8 months 12 days
Deferred tax liabilities assumed	$ 14,000
Subsequent Event | Traveloka
Subsequent Events [Abstract]
Cost investment		$ 350,000