Derivative Instruments and Hedging Activities Options on U.S. Treasury Futures (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative, Notional Amount	$ 18,878,215,000	$ 17,159,801,000	$ 19,137,094,000	$ 23,932,603,000
Options on U.S. Treasury Futures [Member] | U.S. Treasury Futures [Member]
Derivative [Line Items]
Derivative, Notional Amount	2,000,000	0
Fair Value	$ 0	$ 0
Weighted Average Remaining Maturity	50 days	0 days