Segment Information - Schedules of Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net revenue	$ 1,992,523	$ 1,626,373	$ 1,662,991
Cost of goods sold	1,329,551	1,147,214	938,773
Cost of goods sold impairment charges	34,579	126,162	7,815
Gross profit	628,393	352,997	716,403
Selling, general and administrative	326,727	289,598	227,846
Research and development	179,930	188,049	194,190
In-process research and development impairment charges	2,680	46,619	39,259
Acquisition, transaction-related and integration expenses	8,988	16,388	221,818
Restructuring and other charges	2,398	34,345	56,413
Charges (gains) related to legal matters, net	5,860	12,442	(19,711)
Intellectual property legal development expenses	10,655	14,238	16,261
Operating income (loss)	91,155	(248,682)	(19,673)
Generics
Segment Reporting Information [Line Items]
Net revenue	1,343,210	1,308,843	1,439,031
Cost of goods sold		5,000
AvKARE
Segment Reporting Information [Line Items]
Net revenue	293,746	0	0
Operating Segments
Segment Reporting Information [Line Items]
Acquisition, transaction-related and integration expenses		8,346
Intellectual property legal development expenses	8	1,045
Operating Segments | Generics
Segment Reporting Information [Line Items]
Net revenue	1,343,210	1,308,843	1,439,031
Cost of goods sold	894,422	984,782	835,181
Cost of goods sold impairment charges	34,579	119,145	7,815
Gross profit	414,209	204,916	596,035
Selling, general and administrative	56,134	68,883	68,426
Research and development	150,068	172,196	183,412
In-process research and development impairment charges	2,680	46,619	39,259
Acquisition, transaction-related and integration expenses	328	4,633	114,622
Restructuring and other charges	(614)	20,101	33,943
Charges (gains) related to legal matters, net	5,610	12,442	(22,300)
Intellectual property legal development expenses	10,647	13,193	15,772
Operating income (loss)	189,356	(133,151)	162,901
Operating Segments | Specialty
Segment Reporting Information [Line Items]
Net revenue	355,567	317,530	223,960
Cost of goods sold	192,910	162,432	103,592
Cost of goods sold impairment charges	0	7,017	0
Gross profit	162,657	148,081	120,368
Selling, general and administrative	75,917	79,665	49,465
Research and development	29,862	15,853	10,778
In-process research and development impairment charges	0	0	0
Acquisition, transaction-related and integration expenses	85		0
Restructuring and other charges	0	391	4,076
Charges (gains) related to legal matters, net	250	0	0
Intellectual property legal development expenses			489
Operating income (loss)	56,535	42,781	55,560
Operating Segments | AvKARE
Segment Reporting Information [Line Items]
Net revenue	293,746
Cost of goods sold	242,219
Cost of goods sold impairment charges	0
Gross profit	51,527
Selling, general and administrative	58,544
Research and development	0
In-process research and development impairment charges	0
Acquisition, transaction-related and integration expenses	641
Restructuring and other charges	0
Charges (gains) related to legal matters, net	0
Intellectual property legal development expenses	0
Operating income (loss)	(7,658)
Corporate and Other
Segment Reporting Information [Line Items]
Net revenue	0	0	0
Cost of goods sold	0	0	0
Cost of goods sold impairment charges	0	0	0
Gross profit	0	0	0
Selling, general and administrative	136,132	141,050	109,955
Research and development	0	0	0
In-process research and development impairment charges	0	0	0
Acquisition, transaction-related and integration expenses	7,934	3,409	107,196
Restructuring and other charges	3,012	13,853	18,394
Charges (gains) related to legal matters, net	0	0	2,589
Intellectual property legal development expenses	0	0	0
Operating income (loss)	$ (147,078)	$ (158,312)	$ (238,134)