Related Party Transactions - Other Related Party Transactions (Details)				3 Months Ended		6 Months Ended
	Sep. 01, 2023 company shares	Jan. 01, 2023 USD ($)	Jan. 01, 2014 USD ($)	Jun. 30, 2025 USD ($) shares	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) shares	Jun. 30, 2024 USD ($) shares	Jun. 16, 2025 USD ($) shares	Apr. 29, 2025 USD ($) shares	Mar. 14, 2025 USD ($) shares	Dec. 31, 2024 shares
Related Party Transaction [Line Items]
Common stock, shares, issued (in shares) | shares				47,421,929		47,421,929					42,679,569
Number of company owned | company	1
Preferred Class A | NexAnnuity Holdings, Inc.
Related Party Transaction [Line Items]
Stock issued during period, new issues (in shares) | shares	68,500					72,718	65,864
NexPoint Storage Partners Operating Company, LLC
Related Party Transaction [Line Items]
NXDT Percentage Ownership				35.70%		35.70%					29.50%
NexPoint Storage Partners Operating Company, LLC
Related Party Transaction [Line Items]
Number of shares purchased (in shares) | shares								5,157.67	4,638.07	2,754.59
Aggregate amount								$ 3,600,000	$ 3,200,000	$ 2,000,000
NexPoint Storage Partners Operating Company, LLC | Common Class B
Related Party Transaction [Line Items]
Common stock, shares, issued (in shares) | shares				59,615		59,615
Property Management Fees | Cityplace Tower | Reimbursements Member
Related Party Transaction [Line Items]
Cityplace Tower reimbursed				$ 400,000	$ 400,000	$ 800,000	$ 900,000
Property Management Fees | NexVest Realty Advisors
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party						$ 400,000	$ 400,000
Related party transaction, monthly expenses from transactions with related party		$ 1,200	$ 750
Property Management Fees | NexVest Realty Advisors | White Rock Center
Related Party Transaction [Line Items]
Management fee, percent						4.00%
Property Management Fees | NexVest Realty Advisors | Cityplace Tower
Related Party Transaction [Line Items]
Management fee, percent						3.00%
Minimum management fee				20,000		$ 20,000
Management Fee | NexVest Realty Advisors | Cityplace Tower
Related Party Transaction [Line Items]
Minimum management fee				$ 750		$ 750
Management Fee | NexVest Realty Advisors | Undeveloped Land in Plano, Texas
Related Party Transaction [Line Items]
Management fee, percent						3.00%
Guarantor on Loans | NexPoint Storage Partners Operating Company, LLC
Related Party Transaction [Line Items]
NXDT Percentage Ownership				100.00%		100.00%
Guarantor on Loans | White Rock Center
Related Party Transaction [Line Items]
Additional principal amount				$ 10,000,000		$ 10,000,000