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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Investments - Additional Information (Details) € in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2022 USD ($)	Mar. 31, 2022 USD ($) Portfolio	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2022 EUR (€)
Investment Holdings [Line Items]
Aggregate estimated fair value of investments in unrealized loss position		$ 445,100,000
Return of Fountain Healthcare Partners II, L.P. investment		$ 485,000
Synchronicity Pharma Inc \| Investee \| Maximum
Investment Holdings [Line Items]
Equity method investment percentage	50.00%
Synchronicity Pharma Inc \| Convertible Promissory Notes \| Investee
Investment Holdings [Line Items]
Purchase of convertible promissory notes	$ 500,000
Convertible promissory notes, maturity date	Sep. 30, 2022
Fountain Healthcare Partners II
Investment Holdings [Line Items]
Funding commitment as percentage of partnership's total funding		7.00%			7.00%
Equity method commitment \| €					€ 7.8
Number of portfolio sold \| Portfolio		1
Proceeds from sale of portfolio		$ 1,000,000.0		$ 1,100,000
Escrow deposit		100,000
Gain (loss) on sale of investment			$ (300,000)
Return of Fountain Healthcare Partners II, L.P. investment		500,000
Fountain Healthcare Partners II \| Other Assets
Investment Holdings [Line Items]
Carrying value of equity investment		5,800,000		$ 6,100,000
Fountain Healthcare Partners II \| Other Expense, Net
Investment Holdings [Line Items]
Gain (loss) on sale of investment		600,000
Fountain Healthcare Partners II \| Maximum
Investment Holdings [Line Items]
Gain (loss) on sale of investment		$ 100,000