Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details)	1 Months Ended	3 Months Ended	6 Months Ended
	Jan. 31, 2010 contingent_value_right contingent_value_right_series	Jun. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of CVR Series | contingent_value_right_series	4
Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Viking common stock		$ 19,407,000	$ 19,407,000	$ 30,889,000
Transferred over Time | Phase 3 Clinical Trial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross contract asset		10,000,000	10,000,000
Maximum | Transferred over Time | Development, Regulatory, & Commercial Milestones and Tiered Royalties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments		375,000,000	375,000,000
Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of CVRs issued per acquiree share | contingent_value_right	4
Number of CVRs issued from each CVR series | contingent_value_right	1
Frequency of cash payments to CVR holders	6 months
xCella | Earnout Rights for Partner Research and Development
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout rights recognized		500,000	1,000,000
Contingent liabilities - Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mark-to-market adjustment of CVR liability		(400,000)	(1,000,000)
Contingent liabilities - Icagen
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mark-to-market adjustment of CVR liability		200,000	(300,000)
Payment for contingent consideration liabilities		1,500,000
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		142,655,000	142,655,000	321,586,000
Liabilities, fair value		9,291,000	9,291,000	11,157,000
Recurring | Contingent liabilities - CyDex
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		317,000	317,000	349,000
Recurring | Contingent liabilities - Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		2,400,000	2,400,000	3,358,000
Recurring | Contingent liabilities - Icagen
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		5,542,000	5,542,000	7,364,000
Recurring | Contingent liabilities - xCella
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		960,000	960,000	0
Recurring | Amounts owed to former licensor
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		72,000	72,000	86,000
Recurring | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		123,248,000	123,248,000	290,697,000
Recurring | Investment in Viking common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		19,407,000	19,407,000
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		23,993,000	23,993,000	40,624,000
Liabilities, fair value		72,000	72,000	86,000
Recurring | Level 1 | Contingent liabilities - CyDex
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 1 | Contingent liabilities - Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 1 | Contingent liabilities - Icagen
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 1 | Contingent liabilities - xCella
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 1 | Amounts owed to former licensor
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		72,000	72,000	86,000
Recurring | Level 1 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		4,586,000	4,586,000	9,735,000
Recurring | Level 1 | Investment in Viking common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value				30,889,000
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		118,533,000	118,533,000	280,553,000
Liabilities, fair value		2,400,000	2,400,000	3,358,000
Recurring | Level 2 | Contingent liabilities - CyDex
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 2 | Contingent liabilities - Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		2,400,000	2,400,000	3,358,000
Recurring | Level 2 | Contingent liabilities - Icagen
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 2 | Contingent liabilities - xCella
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 2 | Amounts owed to former licensor
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 2 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		118,533,000	118,533,000	280,553,000
Recurring | Level 2 | Investment in Viking common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		0	0	0
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		129,000	129,000	409,000
Liabilities, fair value		6,819,000	6,819,000	7,713,000
Recurring | Level 3 | Contingent liabilities - CyDex
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		317,000	317,000	349,000
Recurring | Level 3 | Contingent liabilities - Metabasis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 3 | Contingent liabilities - Icagen
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		5,542,000	5,542,000	7,364,000
Recurring | Level 3 | Contingent liabilities - xCella
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		960,000	960,000	0
Recurring | Level 3 | Amounts owed to former licensor
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, fair value		0	0	0
Recurring | Level 3 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		129,000	129,000	409,000
Recurring | Level 3 | Investment in Viking common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		$ 0	$ 0	$ 0