Offsetting Assets and Liabilities - Offsetting Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities		$ 23,911
Gross Amounts Offset in the Statement of Financial Condition		0
Net Amounts of Liabilities Presented in the Statement of Financial Condition		23,911
Financial Instruments Collateral		(23,373)
Cash Collateral Pledged		0
Net Amount		538
Cash Collateral Pledged	$ (6,500)	(5,600)
Securities loaned
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	81,049
Gross Amounts Offset in the Statement of Financial Condition	0
Net Amounts of Liabilities Presented in the Statement of Financial Condition	81,049
Financial Instruments Collateral	(78,208)
Cash Collateral Pledged	0
Net Amount	2,841
Derivatives
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	16,147	16,923
Gross Amounts Offset in the Statement of Financial Condition	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Condition	16,147	16,923
Financial Instruments Collateral	0	0
Cash Collateral Pledged	(6,216)	(5,572)
Net Amount	9,931	11,351
Exchange-traded options | Short
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	221	2,774
Gross Amounts Offset in the Statement of Financial Condition	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Condition	221	2,774
Financial Instruments Collateral	0	0
Cash Collateral Pledged	0	0
Net Amount	$ 221	$ 2,774