Goodwill and Other Intangible Assets - Changes in intangible assets (Details) $ in Thousands	3 Months Ended												6 Months Ended			9 Months Ended			12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2013 USD ($)	Mar. 31, 2013 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Balance at beginning of period	$ 699,443	$ 674,687	$ 689,490	$ 704,791	$ 671,127	$ 429,788	$ 122,933	$ 115,900					$ 704,791	$ 115,900		$ 704,791	$ 115,900		$ 704,791	$ 115,900
Amortization of intangibles	17,066	16,545	16,284	16,377	16,483	13,814	8,439	4,757	$ 2,444	$ 1,568	$ 1,677	$ 1,733	32,661	13,196	$ 3,410	49,206	27,010	$ 4,978	66,272	43,493	$ 7,422
Impairment - finite lived intangible assets	30,376																		30,376
Impairment - indefinite lived intangible assets													(2,627)			(2,627)
Balance at end of period	653,628	$ 699,443	$ 674,687	689,490	704,791	$ 671,127	$ 429,788	122,933	115,900				674,687	429,788		699,443	671,127		653,628	704,791	115,900
IPR&D [Member]
Balance at beginning of period				227,259									227,259			227,259			227,259
Indefinite lived acquisitions																			300	227,259
Impairment - indefinite lived intangible assets																			(2,627)
Reclassifications																			(38,000)
Balance at end of period	186,932				227,259														186,932	227,259
VersaPharm [Member]
Impairment - indefinite lived intangible assets																			$ 2,600
Number Of I P R D Projects Abandoned | item																			2
Hi-Tech Pharmacal Co., Inc [Member]
Impairment - finite lived intangible assets																			$ 30,400
Number of currently marketed products with incurred impairment | item																			1
Product Licensing Rights [Member]
Balance at beginning of period				704,791				115,900					704,791	115,900		704,791	115,900		$ 704,791	115,900
Finite lived acquisitions																			3,535	664,627
Amortization of intangibles																			(62,323)	(39,188)
Impairment - finite lived intangible assets																			(30,376)
Dispositions																				(36,548)
Reclassifications																			38,000
Balance at end of period	653,627				704,791				115,900										653,627	704,791	115,900
Trademarks [Member]
Balance at beginning of period				14,279				8,656					14,279	8,656		14,279	8,656		14,279	8,656
Finite lived acquisitions																				6,500
Amortization of intangibles																			(1,261)	(877)
Balance at end of period	13,018				14,279				8,656										13,018	14,279	8,656
Customer Relationships [Member]
Balance at beginning of period				3,035				4,638					3,035	4,638		3,035	4,638		3,035	4,638
Finite lived acquisitions																				300
Amortization of intangibles																			(381)	(1,934)
Foreign currency translation																			123	31
Balance at end of period	2,777				3,035				4,638										2,777	3,035	4,638
Other Intangible Assets [Member]
Balance at beginning of period				10,356									10,356			10,356			10,356
Finite lived acquisitions																				11,234
Amortization of intangibles																			(1,721)	(879)
Balance at end of period	$ 8,635				10,356														8,635	10,356
Noncompete Agreements [Member]
Balance at beginning of period				$ 683				$ 1,311					$ 683	$ 1,311		$ 683	$ 1,311		683	1,311
Amortization of intangibles																			(586)	(615)
Foreign currency translation																			$ (97)	(12)
Balance at end of period					$ 683				$ 1,311											$ 683	$ 1,311