Fair Value Measurements - Notional Amounts and Fair Values of Derivatives by Product (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Derivatives asset, Notional	$ 6,700	$ 14,300
Derivatives asset, Fair Value	6	92
Derivative liability, notional	4,466,700	3,534,300
Derivative liability, Fair Value	1,858	368
TBAs \| Other Contracts
Derivatives, Fair Value [Line Items]
Derivatives asset, Notional	6,700	14,300
Derivatives asset, Fair Value	6	92
Derivative liability, notional	6,700	14,300
Derivative liability, Fair Value	26	81
Future \| Commodity Contracts
Derivatives, Fair Value [Line Items]
Derivative liability, notional	4,460,000	3,520,000
Derivative liability, Fair Value	$ 1,832	$ 287

Nominal or face amount used to calculate payments on the derivative asset.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Nominal or face amount used to calculate payments on the derivative liability.

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