Repurchase Agreements - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($) counterparty	Dec. 31, 2021 USD ($) counterparty
Concentration Risk [Line Items]
Number of counterparties with MRAs	36	34
Carrying amount \| $	$ 6,440,004	$ 3,948,037
Number of counterparties with repurchase agreements outstanding	19	18
Ratio of indebtedness to net capital maximum	12
Counterparty Concentration Risk \| Aggregate Borrowings
Concentration Risk [Line Items]
Number of counterparties	5	2
Counterparty Concentration Risk \| BUCKLER Securities, LLC \| Aggregate Borrowings
Concentration Risk [Line Items]
Percentage of portfolio invested	52.40%	49.70%
Counterparty Concentration Risk \| BUCKLER Securities, LLC \| Stockholders' Equity
Concentration Risk [Line Items]
Percentage of portfolio invested	8.30%	5.00%
Weighted average maturity	16 days	35 days
Counterparty Concentration Risk \| One Repurchase Agreement Counterparty \| Aggregate Borrowings
Concentration Risk [Line Items]
Percentage of portfolio invested	5.00%	5.00%
Counterparty Concentration Risk \| One Repurchase Agreement Counterparty \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of portfolio invested	31.00%	16.00%

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Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Indebtedness divided by net capital.

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