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Investments - Additional Information (Details) $ in Thousands, € in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 31, 2022 USD ($)	Mar. 31, 2022 USD ($) Portfolio	Dec. 31, 2022 USD ($) InvestmentSecurity	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) Portfolio	May 31, 2023 USD ($)	Dec. 31, 2022 EUR (€)	Sep. 30, 2019 USD ($)
Investment Holdings [Line Items]
Aggregate estimated fair value of investments in unrealized loss position			$ 422,700
Number of investment securities \| InvestmentSecurity			289
Number of unrealized investment securities \| InvestmentSecurity			280
Return of Fountain Healthcare Partners II, L.P. investment			$ 485		$ 2,751
Synchronicity Pharma Inc \| Investee \| Other income, net
Investment Holdings [Line Items]
Other-than-temporary impairment charge			$ 500	$ 900	$ 1,000
Synchronicity Pharma Inc \| Convertible Promissory Notes \| Investee
Investment Holdings [Line Items]
Purchase of convertible promissory notes	$ 500							$ 1,900
Convertible promissory notes, maturity date	Sep. 30, 2022		Jun. 30, 2021
Equity method investment percentage	50.00%		50.00%				50.00%
Fountain Healthcare Partners II
Investment Holdings [Line Items]
Equity method commitment \| €							€ 7.4
Funding commitment as percentage of partnership's total funding			7.00%				7.00%
Number of portfolio sold \| Portfolio		1			2
Proceeds from sale of portfolio		$ 1,000		700	$ 10,400
Sale of portfolio, total value		1,100			11,100
Gain (loss) on investment			$ 1,800	(400)	300
Return of Fountain Healthcare Partners II, L.P. investment		500			2,800
Fountain Healthcare Partners II \| Forecast
Investment Holdings [Line Items]
Escrow deposit						$ 100
Fountain Healthcare Partners II \| Other Assets
Investment Holdings [Line Items]
Carrying value of equity investment			$ 7,900	$ 6,100
Fountain Healthcare Partners II \| Maximum
Investment Holdings [Line Items]
Commitment on equity method investment \| €							€ 7.4
Fountain Healthcare Partners II \| Other Income (Expense), Net
Investment Holdings [Line Items]
Gain (loss) on investment		$ 600			$ 8,300
Corporate debt securities
Investment Holdings [Line Items]
Percentage of investment securities available for sale unrealized loss position			47.00%				47.00%
U.S. government and agency debt securities
Investment Holdings [Line Items]
Percentage of investment securities available for sale unrealized loss position			45.00%				45.00%