Repurchase Agreements - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) counterparty	Dec. 31, 2020 USD ($) counterparty
Concentration Risk [Line Items]
Number of counterparties with master repurchase agreements	34	33
Repurchase agreements, carrying amount \| $	$ 3,948,037	$ 4,536,065
Number of counterparties with repurchase agreements outstanding	18	18
Credit Risk and Non-Agency Securities
Concentration Risk [Line Items]
Haircut (as a percent)	3.45%	3.13%
Counterparty Concentration Risk \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Number of counterparties	2	1
Counterparty Concentration Risk \| BUCKLER Securities, LLC \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	49.70%	66.10%
Counterparty Concentration Risk \| BUCKLER Securities, LLC \| Stockholders' Equity, Total
Concentration Risk [Line Items]
Percentage of concentration risk	5.00%	8.30%
Weighted average maturity	35 days	21 days
Counterparty Concentration Risk \| One Repurchase Agreement Counterparty \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	16.00%
Counterparty Concentration Risk \| Two Repurchase Agreement Counterparties \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		9.00%
Minimum \| Counterparty Concentration Risk \| One Repurchase Agreement Counterparty \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	5.00%
Minimum \| Counterparty Concentration Risk \| Two Repurchase Agreement Counterparties \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		5.00%
Maximum
Concentration Risk [Line Items]
Ratio of indebtedness to net capital	12
Maximum \| Counterparty Concentration Risk \| One Repurchase Agreement Counterparty \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	10.00%
Maximum \| Counterparty Concentration Risk \| Two Repurchase Agreement Counterparties \| Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		10.00%

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Haircut on Repurchase Agreements

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Repurchase Agreements, Number Of Counterparties

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Repurchase Agreements, Number Of Counterparties with Outstanding Borrowings

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Repurchase Agreements, Number of Counterparties with Master Repurchase Agreements

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- Definition

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

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Indebtedness divided by net capital.

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