Equity and Other Investments and Fair Value Measurements - Schedule of Available-for-Sale Securities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024		Dec. 31, 2023
Fair Value Measurements
Contingent value rights	$ 325		$ 359
ISP Fund LP
Liabilities
Lock-up period	36 months		36 months
Contributed to partnership for investing	$ 300,000		$ 300,000
Withdrawal from investment	0		0
Money market funds | ISP Fund LP
Assets
Total assets measured at estimated fair value	61,400		62,900
Equity investment | ISP Fund LP
Assets
Total assets measured at estimated fair value	225,700		248,500
Private Placement Positions and Convertible Notes | ISP Fund LP
Assets
Total assets measured at estimated fair value	61,600		60,600
Recurring basis
Assets
Total assets measured at estimated fair value	754,628		705,963
Recurring basis | Money market funds
Assets
Total assets measured at estimated fair value	151,836		170,706
Recurring basis | Equity investments and Money market funds | ISP Fund LP
Assets
Total assets measured at estimated fair value	287,139	[1]	311,812	[2]
Recurring basis | Term loan investment | Armata July 2023 Term Loan
Assets
Total assets measured at estimated fair value	27,426		27,044
Recurring basis | Term loan investment | Armata March 2024 Term Loan
Assets
Total assets measured at estimated fair value	35,479
Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1
Assets
Total assets measured at estimated fair value	482,178		503,162
Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Money market funds
Assets
Total assets measured at estimated fair value	151,836		170,706
Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Equity investments and Money market funds | ISP Fund LP
Assets
Total assets measured at estimated fair value	225,521	[1]	251,207	[2]
Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Term loan investment | Armata July 2023 Term Loan
Assets
Total assets measured at estimated fair value	0		0
Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Term loan investment | Armata March 2024 Term Loan
Assets
Total assets measured at estimated fair value	0
Recurring basis | Significant Other Observable Inputs, Level 2
Assets
Total assets measured at estimated fair value	47,067		35,297
Recurring basis | Significant Other Observable Inputs, Level 2 | Money market funds
Assets
Total assets measured at estimated fair value	0		0
Recurring basis | Significant Other Observable Inputs, Level 2 | Equity investments and Money market funds | ISP Fund LP
Assets
Total assets measured at estimated fair value	0	[1]	0	[2]
Recurring basis | Significant Other Observable Inputs, Level 2 | Term loan investment | Armata July 2023 Term Loan
Assets
Total assets measured at estimated fair value	0		0
Recurring basis | Significant Other Observable Inputs, Level 2 | Term loan investment | Armata March 2024 Term Loan
Assets
Total assets measured at estimated fair value	0
Recurring basis | Significant Unobservable Inputs, Level 3
Assets
Total assets measured at estimated fair value	225,383		167,504
Recurring basis | Significant Unobservable Inputs, Level 3 | Money market funds
Assets
Total assets measured at estimated fair value	0		0
Recurring basis | Significant Unobservable Inputs, Level 3 | Equity investments and Money market funds | ISP Fund LP
Assets
Total assets measured at estimated fair value	61,618	[1]	60,605	[2]
Recurring basis | Significant Unobservable Inputs, Level 3 | Term loan investment | Armata July 2023 Term Loan
Assets
Total assets measured at estimated fair value	27,426		27,044
Recurring basis | Significant Unobservable Inputs, Level 3 | Term loan investment | Armata March 2024 Term Loan
Assets
Total assets measured at estimated fair value	35,479
Nonrecurring basis
Fair Value Measurements
Contingent value rights	325		359
Liabilities
Total liabilities measured at estimated fair value	435,983		427,836
Nonrecurring basis | Debt
Fair Value Measurements
2025 Notes	205,325		200,407
2028 Notes	230,333		227,070
Total fair value of debt	435,658		427,477
Nonrecurring basis | Quoted Price in Active Markets for Identical Assets, Level 1
Fair Value Measurements
Contingent value rights	0		0
Liabilities
Total liabilities measured at estimated fair value	0		0
Nonrecurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Debt
Fair Value Measurements
2025 Notes	0		0
2028 Notes	0		0
Total fair value of debt	0		0
Nonrecurring basis | Significant Other Observable Inputs, Level 2
Fair Value Measurements
Contingent value rights	0		0
Liabilities
Total liabilities measured at estimated fair value	435,658		427,477
Nonrecurring basis | Significant Other Observable Inputs, Level 2 | Debt
Fair Value Measurements
2025 Notes	205,325		200,407
2028 Notes	230,333		227,070
Total fair value of debt	435,658		427,477
Nonrecurring basis | Significant Unobservable Inputs, Level 3
Fair Value Measurements
Contingent value rights	325		359
Liabilities
Total liabilities measured at estimated fair value	325		359
Nonrecurring basis | Significant Unobservable Inputs, Level 3 | Debt
Fair Value Measurements
2025 Notes	0		0
2028 Notes	0		0
Total fair value of debt	0		0
Armata | Recurring basis | Convertible debt investment
Assets
Total assets measured at estimated fair value	64,254		51,883
Armata | Recurring basis | Equity investment | Common stock
Assets
Total assets measured at estimated fair value	104,821		81,249
Armata | Recurring basis | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	47,067		35,297
Armata | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
Armata | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Equity investment | Common stock
Assets
Total assets measured at estimated fair value	104,821		81,249
Armata | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	0		0
Armata | Recurring basis | Significant Other Observable Inputs, Level 2 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
Armata | Recurring basis | Significant Other Observable Inputs, Level 2 | Equity investment | Common stock
Assets
Total assets measured at estimated fair value	0		0
Armata | Recurring basis | Significant Other Observable Inputs, Level 2 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	47,067		35,297
Armata | Recurring basis | Significant Unobservable Inputs, Level 3 | Convertible debt investment
Assets
Total assets measured at estimated fair value	64,254		51,883
Armata | Recurring basis | Significant Unobservable Inputs, Level 3 | Equity investment | Common stock
Assets
Total assets measured at estimated fair value	0		0
Armata | Recurring basis | Significant Unobservable Inputs, Level 3 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	0		0
InCarda | Recurring basis | Convertible debt investment
Assets
Total assets measured at estimated fair value	436
InCarda | Recurring basis | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	75
InCarda | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
InCarda | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	0
InCarda | Recurring basis | Significant Other Observable Inputs, Level 2 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
InCarda | Recurring basis | Significant Other Observable Inputs, Level 2 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	0
InCarda | Recurring basis | Significant Unobservable Inputs, Level 3 | Convertible debt investment
Assets
Total assets measured at estimated fair value	436
InCarda | Recurring basis | Significant Unobservable Inputs, Level 3 | Equity investment | Warrants
Assets
Total assets measured at estimated fair value	75
ImaginAb | Recurring basis | Convertible debt investment
Assets
Total assets measured at estimated fair value	2,894
ImaginAb | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
ImaginAb | Recurring basis | Significant Other Observable Inputs, Level 2 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0
ImaginAb | Recurring basis | Significant Unobservable Inputs, Level 3 | Convertible debt investment
Assets
Total assets measured at estimated fair value	2,894
Gate Neuroscience [Member] | Recurring basis | Convertible debt investment
Assets
Total assets measured at estimated fair value	33,201		27,972
Gate Neuroscience [Member] | Recurring basis | Quoted Price in Active Markets for Identical Assets, Level 1 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0		0
Gate Neuroscience [Member] | Recurring basis | Significant Other Observable Inputs, Level 2 | Convertible debt investment
Assets
Total assets measured at estimated fair value	0		0
Gate Neuroscience [Member] | Recurring basis | Significant Unobservable Inputs, Level 3 | Convertible debt investment
Assets
Total assets measured at estimated fair value	$ 33,201		$ 27,972

[1] The investments held by ISP Fund LP consisted of $225.7 million in equity investments, which included private placement positions of $61.6 million, and $61.4 million in money market funds, cash and interest receivable. A certain portion of the total capital contribution of $300.0 million is no longer subject to a 36-month lock-up period from the date of such capital contribution. However, we did not elect to make a withdrawal in 2023, thereby extending the lock-up period and withdrawal elections into subsequent years.

[2] The investments held by ISP Fund LP, consisted of $248.5 million in equity investments, which included private placement positions of $60.6 million, and $62.9 million in money market funds. A certain portion of the total capital contribution of $300.0 million is no longer subject to a 36-month lock-up period from the date of such capital contribution. However, we did not elect to make a withdrawal in 2023, thereby extending the lock-up period and withdrawal elections into subsequent years.