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v3.25.3

Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Development fees | $ 1,157 | $ 6,143
Vornado |  |
Development fees | $ 182 | $ 192

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- Definition Non-cash additions to real estate included in accounts payable and accrued expenses. + References No definition available. + Details
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Namespace Prefix: | alx_
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Balance Type: | debit
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |