Strategic Alliances (Details) - USD ($)						1 Months Ended		3 Months Ended								12 Months Ended			84 Months Ended
	Sep. 14, 2021	Jul. 06, 2021	Jun. 18, 2021	May 05, 2020	Oct. 21, 2019	May 31, 2016	Jan. 31, 2015	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues								$ 401,332,000	$ 385,813,000	$ 442,408,000	$ 545,165,000	$ 494,676,000	$ 428,064,000	$ 301,207,000	$ 211,466,000	$ 1,774,718,000	$ 1,435,413,000	$ 901,935,000
Contract liability								466,000				$ 16,378,000				466,000	16,378,000		$ 466,000
Milestone revenue recognized																15,911,000
LeaderMed | LenderMed Joint Venture | Corporate Joint Venture
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Ownership interest in joint venture (as a percent)	47.00%
Initial investment in joint venture	$ 11,000,000
Ownership percentage by related parties (as a percent)	53.00%
CAMP4
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payment (in shares)		3,373,008
Outstanding shares (as a percent)		9.00%
Period following first commercial sale in a country		10 years
Nicoya
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payment from development and license agreement			$ 5,000,000
Period after first commercial sale			10 years
Pfizer | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Annual height velocity at point in time					12 months
Phase Three Initiation | Nicoya
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payment from development and license agreement			$ 5,000,000
Regulatory and Development | Nicoya
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment from development and license agreement			$ 115,000,000
Revenue from transfer of intellectual property and other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues																25,842,000	53,219,000	73,317,000
Revenue from transfer of intellectual property and other | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues				$ 3,000,000													3,000,000
Revenue from transfer of intellectual property and other | LeaderMed | LenderMed Joint Venture | Corporate Joint Venture
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	$ 1,000,000															1,000,000
Revenue from transfer of intellectual property and other | LeaderMed | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues																1,000,000
Revenue from transfer of intellectual property and other | CAMP4
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues		$ 1,500,000
Revenue from transfer of intellectual property and other | CAMP4 | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues									$ 4,900,000							4,900,000
Revenue from transfer of intellectual property and other | Nicoya | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues																5,000,000
Revenue from transfer of intellectual property and other | Pfizer | Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues																10,800,000	28,700,000	66,800,000
Dravet Syndrome Products | CAMP4
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Development milestone payments		3,500,000
Sales milestone payments		$ 90,000,000
Development milestone payments (in shares)		5,782,299
Non-Dravet Syndrome Products | CAMP4
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Development milestone payments		$ 4,000,000
Sales milestone payments		$ 90,000,000
Development milestone payments (in shares)		1,082,248
Product registrations
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues																141,770,000	$ 119,952,000	$ 112,184,000
Product registrations | Pfizer
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Non-refundable upfront payment							$ 295,000,000									295,000,000
Additional milestone payment to be received							275,000,000
Contract liability								$ 0								$ 0			0
Additional milestone payment							275,000,000
Milestone revenue recognized																			$ 0
Product registrations | Minimum | Pfizer
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment ranges							20,000,000
Product registrations | Maximum | Pfizer
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment ranges							$ 90,000,000
Regulatory Milestones | Rayaldee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payment to be received				17,000,000
Sales Milestones | Rayaldee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payment to be received				$ 210,000,000
Exclusive Option | Vifor Fresenius Medical Care Pharma Ltd
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payment to be received						$ 555,000,000