Shareholders' Deficit - Schedule of Changes in Shareholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	$ (498,283)	$ 484,880
Effect of adopting accounting principle in period of adoption			$ (4,646)		$ 3,076
Shareholders' equity, adjusted beginning balance			(502,929)		487,956
Net income (loss)	(18,573)	(505,489)
Other comprehensive income (loss)	4,730	(5,797)
Compensation related to share-based awards	24,733	17,890
Exercise of options	4
Tax withholding for restricted shares	(2,414)	(1,642)
Other	(1)	(11)
Shareholders' equity, ending balance	(494,450)	(7,093)
Accumulated deficit	(9,148,151)			$ (9,124,932)
Euro Deferred Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	46	48
Shareholders' equity, adjusted beginning balance			46		48
Other	(1)	1
Shareholders' equity, ending balance	45	49
Ordinary Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	22	22
Shareholders' equity, adjusted beginning balance			22		22
Shareholders' equity, ending balance	22	22
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	8,855,810	8,791,170
Shareholders' equity, adjusted beginning balance			8,855,810		8,791,170
Compensation related to share-based awards	24,733	17,890
Exercise of options	4
Tax withholding for restricted shares	(2,414)	(1,642)
Other		(12)
Shareholders' equity, ending balance	8,878,133	8,807,406
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	(9,124,932)	(8,096,539)
Effect of adopting accounting principle in period of adoption			(4,646)		3,076
Shareholders' equity, adjusted beginning balance			(9,129,578)		(8,093,463)
Net income (loss)	(18,573)	(505,489)
Shareholders' equity, ending balance	(9,148,151)	(8,598,952)
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shareholders' equity, beginning balance	(229,229)	(209,821)
Shareholders' equity, adjusted beginning balance			$ (229,229)		(209,821)
Other comprehensive income (loss)	4,730	(5,797)
Shareholders' equity, ending balance	$ (224,499)	$ (215,618)
Effect of adoption of ASC 606 | ASC 606
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated deficit					$ 3,100