Derivative Instruments (Offsetting Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Derivatives Assets
Gross Amounts of Recognized Financial Instruments	$ 11,613,891	$ 9,045,718
Gross Amounts Offset in the Consolidated Statement of Financial Position	(11,606,316)	(9,028,019)
Net Amounts Presented in the Consolidated Statement of Financial Position	7,575	17,699
Financial Instruments/Collateral	0	0
Net Amount	7,575	17,699
Securities Purchased under Agreements to Resell
Gross Amounts of Recognized Financial Instruments	275,000	25,000
Gross Amounts Offset in the Consolidated Statement of Financial Position	0	0
Net Amounts Presented in the Consolidated Statement of Financial Position	275,000	25,000
Financial Instruments/Collateral	0	0
Net Amount	275,000	25,000
Total Assets
Gross Amounts of Recognized Financial Instruments	11,888,891	9,070,718
Gross Amounts Offset in the Consolidated Statement of Financial Position	(11,606,316)	(9,028,019)
Net Amounts Presented in the Consolidated Statement of Financial Position	282,575	42,699
Financial Instruments/Collateral	0	0
Net Amount	282,575	42,699
Derivatives Liabilities
Gross Amounts of Recognized Financial Instruments	22,037,730	21,248,026
Gross Amounts Offset in the Consolidated Statement of Financial Position	(20,039,444)	(18,596,679)
Net Amounts Presented in the Consolidated Statement of Financial Position	1,998,286	2,651,347
Financial Instruments/Collateral	(1,998,286)	(2,651,347)
Net Amount	0	0
Securities Sold under Agreements to Repurchase
Gross Amounts of Recognized Financial Instruments	0	0
Gross Amounts Offset in the Consolidated Statement of Financial Position	0	0
Net Amounts Presented in the Consolidated Statement of Financial Position	0	0
Financial Instruments/Collateral	0	0
Net Amount	0	0
Total Liabilities
Gross Amounts of Recognized Financial Instruments	22,037,730	21,248,026
Gross Amounts Offset in the Consolidated Statement of Financial Position	(20,039,444)	(18,596,679)
Net Amounts Presented in the Consolidated Statement of Financial Position	1,998,286	2,651,347
Financial Instruments/Collateral	(1,998,286)	(2,651,347)
Net Amount	$ 0	$ 0