Payments For Derivative Instrument

No definition available.

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Namespace Prefix:	alx_
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Period Type:	duration

- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Fair Value Measurements - Summarizes Of Interest Rate Derivatives (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jul. 16, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Included in other assets	$ 38,407		$ 29,351
Payments for derivative instrument	11,258
Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payments for derivative instrument	$ 11,258
LIBOR \| Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest cap rate	6.00%
LIBOR \| Mortgages \| Subsequent Event
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest cap rate		6.00%
Prime Rate \| Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate	8.25%
731 Lexington Avenue Mortgage Loan, Retail Condominium \| Interest rate swap \| Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Included in other assets	$ 24,189		26,718
Notional Amount	$ 300,000
Swapped Rate	1.76%
Rego Park II Shopping Center Mortgage Loan \| Interest rate swap \| Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Included in other assets	$ 3,106		2,622
Notional Amount	$ 202,544
Rego Park II Shopping Center Mortgage Loan \| Interest rate swap \| Designated as Hedging Instrument \| SOFR
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest cap rate	4.15%
731 Lexington Avenue Mortgage Loan, Office Condominium \| Interest rate swap \| Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Included in other assets	$ 11,112		$ 11
Notional Amount	$ 500,000
731 Lexington Avenue Mortgage Loan, Office Condominium \| Interest rate swap \| Designated as Hedging Instrument \| LIBOR \| Subsequent Event
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest cap rate		6.00%