Derivative Instruments - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Derivative [Line Items]
Cash collateral payable to trade counterparties	$ 7,800		$ 2,900
Cash collateral received	6,500		5,600
Gains (losses) on equity options activity	(2,000)	$ 4,800
Exchange-traded options \| Long
Derivative [Line Items]
Cash collateral payable to trade counterparties	0		0
Long exchange-traded equity options	400		1,900
Exchange-traded options \| Short
Derivative [Line Items]
Cash collateral received	0		0
Short exchange-traded equity options, included in securities sold not yet purchased	$ 200		$ 2,800

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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Aggregate net gain and losses (whether realized or unrealized) on all derivative instruments held for trading purposes whether or not settled physically.

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