The Company and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended								1 Months Ended	3 Months Ended	9 Months Ended	0 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2014 Customer	Sep. 30, 2013	Sep. 30, 2014 Customer	Sep. 30, 2013	Dec. 31, 2013 Customer	Sep. 30, 2014 Express Scripts [Member]	Dec. 31, 2013 Express Scripts [Member]	Sep. 30, 2014 Idis Limited [Member]	Sep. 30, 2014 Accredo Health Group, Inc. [Member]	Dec. 31, 2013 Accredo Health Group, Inc. [Member]	Feb. 20, 2014 Gentium [Member]	Aug. 31, 2014 Gentium [Member]	Sep. 30, 2014 Gentium [Member]	Feb. 20, 2014 Gentium [Member] Ordinary Options and American Depositary Shares [Member]	Feb. 20, 2014 Gentium [Member] Ordinary Options and American Depositary Shares [Member]	Sep. 30, 2014 Xyrem [Member] application	Sep. 30, 2013 Xyrem [Member]	Sep. 30, 2014 Xyrem [Member] application	Sep. 30, 2013 Xyrem [Member]	Sep. 30, 2014 Erwinaze And Erwinase [Member]	Sep. 30, 2013 Erwinaze And Erwinase [Member]	Sep. 30, 2014 Erwinaze And Erwinase [Member]	Sep. 30, 2013 Erwinaze And Erwinase [Member]	Sep. 30, 2014 Sales Revenue, Product Line [Member] Product Concentration Risk [Member] Xyrem [Member]	Sep. 30, 2014 Sales Revenue, Product Line [Member] Product Concentration Risk [Member] Xyrem [Member]	Sep. 30, 2014 Sales Revenue, Product Line [Member] Product Concentration Risk [Member] Erwinaze And Erwinase [Member]	Sep. 30, 2014 Sales Revenue, Product Line [Member] Product Concentration Risk [Member] Erwinaze And Erwinase [Member]	Dec. 31, 2013 Reclassification of Inventories [Member]	Sep. 30, 2014 Minimum [Member]	Sep. 30, 2014 Maximum [Member]	Sep. 30, 2014 Convertible Debt 2021 Notes [Member]	Aug. 31, 2014 Convertible Debt 2021 Notes [Member]	Sep. 30, 2014 Pending Litigation [Member] Xyrem [Member] lawsuit
Summary Of Significant Accounting Policies [Line Items]
Ownership interest acquired, percentage															98.00%
Additional interest acquired, percentage												1.80%		12.00%
Acquisition cost of noncontrolling interest			$ 136,950,000	$ 0								$ 17,800,000
Net acquisition consideration													994,000,000
Total acquisition consideration, including subsequent acquisition													1,011,100,000
Proceeds from exercise of acquired share options											17,100,000
Amount reclassified																												1,400,000
Product sales, net	$ 304,407,000	$ 230,386,000	$ 838,493,000	$ 631,602,000												$ 204,337,000	$ 153,664,000	$ 556,081,000	$ 404,932,000	$ 52,121,000	$ 44,078,000	$ 146,910,000	$ 130,754,000
Percentage of product sales, net																								67.10%	66.30%	17.10%	17.50%
Number of ANDAs filed by third parties																5		5
Number of lawsuits filed																																	4
Intangible assets, useful life																													2 years	16 years
Number of customers with significant accounts receivable	5		5		5
Percentage of gross accounts receivable	86.00%		86.00%		85.00%	62.00%	69.00%	10.00%	11.00%	9.00%
Debt conversion price (in dollars per share)																																$ 199.77
Number of shares issuable from exchangeable senior notes																															2.9