Significant Accounting Policies - Annual (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Organization [Line Items]
Liabilities		$ 7,452,460	$ 6,659,078
Assets		8,748,814	7,828,199
Subsequent Event
Organization [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock	1,565
Variable Interest Entity, Primary Beneficiary [Member]
Organization [Line Items]
Liabilities		9,800	10,100
Assets		$ 304,100	$ 325,500
Telecommunication and computer equipment | Minimum
Organization [Line Items]
Property, Plant and Equipment, Useful Life		3 years
Telecommunication and computer equipment | Maximum
Organization [Line Items]
Property, Plant and Equipment, Useful Life		5 years
Computer software | Minimum
Organization [Line Items]
Property, Plant and Equipment, Useful Life		3 years
Computer software | Maximum
Organization [Line Items]
Property, Plant and Equipment, Useful Life		4 years
Furniture and fixtures
Organization [Line Items]
Property, Plant and Equipment, Useful Life		5 years
Hedge Funds | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		2.00%
During investment period | Minimum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		1.00%
During investment period | Maximum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		2.00%
During investment period | Other Healthcare Royalty Partners | Minimum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		0.20%
During investment period | Other Healthcare Royalty Partners | Maximum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		1.00%
After investment period | Healthcare Royalty Partners | Minimum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		1.00%
After investment period | Healthcare Royalty Partners | Maximum | Operating Company
Organization [Line Items]
Asset Management Fees, Percent Fee		2.00%