Acquisitions - Cayan - Consideration and Recognized Assets and Liabilities (Details) - USD ($) $ in Thousands		6 Months Ended
	Jan. 11, 2018	Jun. 30, 2018	Dec. 31, 2017
Recognized amounts of identifiable assets acquired and liabilities assumed:
Goodwill		$ 4,088,579	$ 3,264,071
Cayan
Recognized amounts of identifiable assets acquired and liabilities assumed:
Cash paid	$ 1,054,931	1,200
Fair value of total consideration transferred	1,054,931
Cash	16,856
Accounts receivable	16,846
Property, plant and equipment	20,321
Total acquired identifiable intangible assets	324,900
Other assets	3,919
Identifiable intangible assets	324,885	3,300
Total identifiable net assets	235,253
Deferred tax liability	(113,828)
Other liabilities	(33,746)
Goodwill	819,678	$ 11,700
Total identifiable assets acquired and liabilities assumed	$ 1,054,931