Derivative Instruments (Offsetting Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Offsetting of Financial Assets, Derivatives
Gross Amounts of Recognized Financial Instruments	$ 7,086,534	$ 397,546
Gross Amounts Offset in the Consolidated Statement of Financial Position	(6,818,009)	(379,399)
Net Amounts Presented in the Consolidated Statement of Financial Position	268,525	18,147
Financial Instruments/Collateral	0	(14,572)
Net Amount	268,525	3,575
Securities purchased under agreements to resell
Gross Amounts of Recognized Financial Instruments	185,000	0
Gross Amounts Offset in the Consolidated Statement of Financial Position	0	0
Net Amounts Presented in the Consolidated Statement of Financial Position	185,000	0
Financial Instruments/Collateral	(185,000)	0
Net Amount	0	0
Total Assets
Gross Amounts of Recognized Financial Instruments	7,271,534	397,546
Gross Amounts Offset in the Consolidated Statement of Financial Position	(6,818,009)	(379,399)
Net Amounts Presented in the Consolidated Statement of Financial Position	453,525	18,147
Financial Instruments/Collateral	(185,000)	(14,572)
Net Amount	268,525	3,575
Offsetting of Financial Liabilities, Derivatives
Gross Amounts of Recognized Financial Instruments	12,573,983	265,826
Gross Amounts Offset in the Consolidated Statement of Financial Position	(12,568,082)	(265,826)
Net Amounts Presented in the Consolidated Statement of Financial Position	5,901	0
Financial Instruments/Collateral	(5,901)	0
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	12,573,983	265,826
Gross Amounts Offset in the Consolidated Statement of Financial Position	(12,568,082)	(265,826)
Net Amounts Presented in the Consolidated Statement of Financial Position	5,901	0
Financial Instruments/Collateral	(5,901)	0
Net Amount	$ 0	$ 0