Intangible Assets, net - Narrative (Details) (USD $)	3 Months Ended	12 Months Ended	9 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2013 product	Dec. 31, 2014 product	Sep. 30, 2014 annual_IPRD_group	Sep. 28, 2012	Dec. 31, 2012	Dec. 31, 2013	Nov. 06, 2012 product drug_application
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of products associated with IPR&D (projects)	5	8
IPR&D [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of products associated with IPR&D (projects)		2
Par Sterile [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of discontinued products		1
Number of In Process Research and Development Groups Created			6
Par Sterile [Member] | Developed Technology Rights [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Weighted average amortization period			9 years
Par Sterile [Member] | Trade Names [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Weighted average amortization period			5 years
Anchen Acquisition [Member] | IPR&D [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Asset impairment charges				$ 2,000,000
Sky Growth Merger [Member] | Subsequently Developed In Process Research and Development [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Weighted average amortization period		7 years
Watson/Actavis Divestiture Products [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of generic products with marketing rights acquired through merger (products)							5
Number of abbreviated new drug applications awaiting regulatory approval (products)							8
Successor [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Intangible asset impairment		146,934,000			0	100,093,000
Successor [Member] | Sky Growth Merger [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of products associated with IPR&D (projects)		58
Successor [Member] | Sky Growth Merger [Member] | Sky Growth Merger Developed Product Intangible Assets [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Weighted average amortization period		5 years
Successor [Member] | Watson/Actavis Divestiture Products [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Number of generic products with marketing rights acquired through merger (products)							5
Number of abbreviated new drug applications awaiting regulatory approval (products)							8
Successor [Member] | Watson/Actavis Divestiture Products [Member] | Watson/Actavis Divestiture Products [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Weighted average amortization period		5 years
Successor [Member] | Selling, General and Administrative Expenses [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Amortization expense related to intangible assets		184,800,000			42,800,000	184,300,000
Predecessor [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Intangible asset impairment				5,700,000
Predecessor [Member] | Anchen Acquisition [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Asset impairment charges				3,700,000
Predecessor [Member] | Selling, General and Administrative Expenses [Member]
Intangible Assets, Net (Excluding Goodwill) [Line Items]
Amortization expense related to intangible assets				$ 31,200,000