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Related Party Transaction, Renewal Term

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Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Nonvested, Fair Value

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Amount of fee payable for management of fund or trust.

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Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

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Amount of expense for professional and contracted services.

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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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Amount of noncash expense for share-based payment arrangement.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Transactions With Related Parties - Our Manager (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Related Party Transaction [Line Items]
Management fee payable	$ 14,641		$ 14,641		$ 16,434
Non-cash compensation expense	$ 6,675	$ 7,303	$ 13,362	$ 14,268
Common stock, shares outstanding (in shares)	168,543,591		168,543,591		168,259,023
Restricted Class A Common Stock
Related Party Transaction [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	2,001,632		2,001,632		2,174,931
Restricted shares, vesting period (in years)			3 years
Related Party
Related Party Transaction [Line Items]
Common stock, shares outstanding (in shares)	13,764,005		13,764,005
Percentage of stock	8.20%		8.20%
Subsidiary of Common Parent
Related Party Transaction [Line Items]
Common stock, shares outstanding (in shares)	8,916,412		8,916,412
Percentage of stock	5.30%		5.30%
Director \| Deferred Stock Units
Related Party Transaction [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	369,548		369,548
Manager \| Related Party
Related Party Transaction [Line Items]
Renewal term (in years)			1 year
Management fees paid to manager	$ 14,800	17,200	$ 31,200	35,800
Expenses	$ 400	200	$ 800	400
Manager \| Related Party \| Restricted Class A Common Stock
Related Party Transaction [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	1,008,941		1,008,941
Aggregate grant fair value			$ 20,500
Restricted shares, vesting period (in years)			3 years
Non-cash compensation expense	$ 3,500	$ 3,600	$ 7,000	$ 7,200
BXMT Advisors Limited Liability Company and Affiliates \| Related Party
Related Party Transaction [Line Items]
Management fee payable	$ 14,600		$ 14,600		$ 16,400