Available for Sale Debt Securities - Narrative (Details) $ in Millions		1 Months Ended	3 Months Ended
	Jan. 07, 2022 USD ($) payment tranche	Sep. 30, 2022 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Long term funding partnership, amount	$ 300
Long term funding partnership, number of tranches | tranche	5
Long term funding partnership, initial payment	$ 50
Long term funding partnership, additional payments, aggregate amount	200
Long term funding partnership, optional amount unavailable	$ 75
Installment repayments, percentage of amount drawn	1.9
Number of consecutive quarterly payments | payment	34
Long term funding partnership, expected payment			$ 175
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Debt and Equity Securities, FV-NI [Line Items]
Maximum commitment to fund collaborative arrangement				$ 475
Development fund bond
Debt and Equity Securities, FV-NI [Line Items]
Maximum commitment to fund collaborative arrangement		$ 300
MorphoSys
Debt and Equity Securities, FV-NI [Line Items]
Redemption price, percentage		2.2
MorphoSys | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Debt and Equity Securities, FV-NI [Line Items]
Period of return (in years)		9 years
Cytokinetics Funding Commitments
Debt and Equity Securities, FV-NI [Line Items]
Required amount to be drawn	$ 50
Long term funding partnership, expected payment			$ 125