Repurchase Agreements, net - Additional Information (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2026 USD ($) counterparty	Dec. 31, 2025 USD ($) counterparty
Concentration Risk [Line Items]
Number of counterparties with master repurchase agreements	36	35
Repurchase agreements, carrying amount \| $	$ 19,441,457	$ 17,941,796
Number of counterparties with repurchase agreements outstanding	25	22
Ratio of indebtedness to net capital	12
Collateralized Mortgage-Backed Securities
Concentration Risk [Line Items]
Average haircut (as a percent)	2.51%	2.63%
Aggregate Borrowings \| Counterparty Concentration Risk
Concentration Risk [Line Items]
Number of counterparties	2	2
BUCKLER Securities, LLC \| Aggregate Borrowings \| Counterparty Concentration Risk
Concentration Risk [Line Items]
Percentage of concentration risk	46.80%	47.00%
BUCKLER Securities, LLC \| Stockholders' Equity \| Counterparty Concentration Risk
Concentration Risk [Line Items]
Percentage of concentration risk	6.80%	7.10%
Weighted average maturity (in days)	27 days	13 days
Three Repurchase Agreement Counterparties \| Aggregate Borrowings \| Counterparty Concentration Risk
Concentration Risk [Line Items]
Percentage of concentration risk	5.00%	5.00%
Three Repurchase Agreement Counterparties \| Repurchase Agreement Borrowings \| Counterparty Concentration Risk
Concentration Risk [Line Items]
Percentage of concentration risk	10.80%	12.10%

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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.

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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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