Income Taxes - Carryforwards (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 26,510	$ 26,335	$ 26,985
U.S. federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	4,000
Capital loss carryforwards	101,300
Income tax credit carryforwards	700
U.S. state
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	1,400
Net operating loss carryforwards	18,400
Income tax credit carryforwards	400
U.S. state | Capital Loss Carryforward
Operating Loss Carryforwards [Line Items]
Valuation allowance	500
Domestic Tax Authority | Capital Loss Carryforward
Operating Loss Carryforwards [Line Items]
Valuation allowance	25,700
Foreign Tax Authority | Loss and Other Credit Carryforward
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 300