Fair Value of Assets and Liabilities - Assets and Liabilities (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value	$ 52,000	$ 0
(Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value	0	0
(Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value	52,000	0
(Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value	0	0
Seaport Innovation LLC | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	73,217,000	73,471,000
Seaport Innovation LLC | (Level 1) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	0	0
Seaport Innovation LLC | (Level 2) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	0	0
Seaport Innovation LLC | (Level 3) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	$ 73,217,000	$ 73,471,000
Holding period	10 years	10 years
Seaport Innovation LLC | (Level 3) | Corporate Joint Venture | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0700	0.0700
Seaport Innovation LLC | (Level 3) | Corporate Joint Venture | Exit Capitalization Rates
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0600	0.0600
The LSMD Fund REIT LLC | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	$ 46,405,000	$ 46,655,000
The LSMD Fund REIT LLC | (Level 1) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	0	0
The LSMD Fund REIT LLC | (Level 2) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	0	0
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in affiliates, fair value	$ 46,405,000	$ 46,655,000
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Holding period	10 years	10 years
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Holding period		12 years
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Discount Rate | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0625	0.0625
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Discount Rate | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0875	0.0875
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Exit Capitalization Rates | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0525	0.0525
The LSMD Fund REIT LLC | (Level 3) | Corporate Joint Venture | Exit Capitalization Rates | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Measurement input	0.0800	0.0800