Disclosures About Offsetting Assets and Liabilities - Financial Liabilities and Derivative Liabilities that are Subject to Offset (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities, Securities lending	$ (400,000)	$ (178,928)
Net amounts presented in the Statement of Financial Condition, Securities lending	(400,000)	(178,928)
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities lending	71,445	74,488
Gross amounts not offset in the Statement of Financial Position, Collateral pledged, Securities lending	328,495	104,434
Securities lending, Net amount	(60)	(6)
Gross amounts of recognized liabilities, Securities purchased under agreements to resell	(719,432)	(580,170)
Net amounts presented in the Statement of Financial Condition, Securities purchased under agreements to resell	(719,432)	(580,170)
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities purchased under agreements to resell	10,307	63,771
Gross amounts not offset in the Statement of Financial Position, Collateral pledged, Securities purchased under agreements to resell	709,125	516,399
Gross amounts of recognized liabilities	(1,201,785)	(869,923)
Net amounts presented in the Statement of Financial Condition	(1,201,785)	(869,923)
Gross amounts not offset in the Statement of Financial Position, Financial instruments	96,659	143,882
Gross amounts not offset in the Statement of Financial Condition, Collateral pledged	1,048,417	651,559
Net amount	(56,709)	(74,482)
Interest Rate Contracts [Member]
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	(82,353)	(110,825)
Net amounts presented in the Statement of Financial Condition	(82,353)	(110,825)
Gross amounts not offset in the Statement of Financial Position, Financial instruments	14,907	5,623
Gross amounts not offset in the Statement of Financial Condition, Collateral pledged	10,797	30,726
Offsetting liability interest rate contracts net	$ (56,649)	$ (74,476)