Derivative Instruments Effective Date

No definition available.

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Namespace Prefix:	ahh_
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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
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Period Type:	duration

- 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

No definition available.

+ Details

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Period Type:	duration

- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)			6 Months Ended
	Jul. 13, 2015	Feb. 20, 2015	Jun. 30, 2015	Dec. 31, 2014
Derivative [Line Items]
Notional Amount			$ 222,221,000	$ 181,119,000
Senior unsecured term loan facility		$ 50,000,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Amount			$ 50,675,000	$ 685,000
One-month LIBOR [Member] \| Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Amount		$ 50,000,000
Fixed rate interest rate swap		2.00%
Fixed rate interest rate swap, agreement date			Feb. 20, 2015
Fixed rate interest rate swap, Maturity date			Feb. 20, 2020
Fixed rate interest rate swap, Effective date			Mar. 01, 2016
One-month LIBOR [Member] \| Interest Rate Swaps [Member] \| Subsequent Event [Member]
Derivative [Line Items]
Notional Amount	$ 6,500,000
Fixed rate interest rate swap	3.05%
Fixed rate interest rate swap, agreement date	Jul. 13, 2015
Fixed rate interest rate swap, Maturity date	Apr. 05, 2018
Fixed rate interest rate swap, Effective date	Jul. 13, 2015
LIBOR [Member] \| Minimum [Member] \| Senior Unsecured Term Loan Facility [Member]
Derivative [Line Items]
Senior unsecured term loan facility interest rate		1.35%
LIBOR [Member] \| Maximum [Member] \| Senior Unsecured Term Loan Facility [Member]
Derivative [Line Items]
Senior unsecured term loan facility interest rate		1.95%