Derivative Instruments Effective Date

No definition available.

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Namespace Prefix:	ahh_
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- Definition

Premiums paid on derivative instruments.

+ References

No definition available.

+ Details

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

- 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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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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Balance Type:	na
Period Type:	duration

- 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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Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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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- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
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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Derivative Financial Instruments - Additional Information (Detail) (USD $)	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Feb. 20, 2015	Dec. 31, 2013	Mar. 14, 2014
Derivative [Line Items]
Interest rate agreement, notional amount	181,119,000invest_DerivativeNotionalAmount		$ 131,377,000invest_DerivativeNotionalAmount
Subsequent Event [Member]
Derivative [Line Items]
Senior unsecured term loan facility		50,000,000
Pay Fixed Interest Rate Swaps [Member]
Derivative [Line Items]
Interest rate agreement, notional amount	685,000		705,000
Interest Rate Caps [Member]
Derivative [Line Items]
Interest rate agreement, notional amount	180,434,000		130,672,000
One Month Libor [Member] \| Pay Fixed Interest Rate Swaps [Member]
Derivative [Line Items]
Fixed rate interest rate swap, Maturity date	Feb. 20, 2020
Fixed rate interest rate swap, agreement date	Feb. 20, 2015
Fixed rate interest rate swap, Effective date	Mar. 01, 2016
One Month Libor [Member] \| Pay Fixed Interest Rate Swaps [Member] \| Subsequent Event [Member]
Derivative [Line Items]
Interest rate agreement, notional amount		50,000,000
Fixed rate interest rate swap		2.00%
LIBOR [Member] \| Subsequent Event [Member] \| Minimum [Member]
Derivative [Line Items]
Senior unsecured term loan facility interest rate		1.35%
LIBOR [Member] \| Subsequent Event [Member] \| Maximum [Member]
Derivative [Line Items]
Senior unsecured term loan facility interest rate		1.95%
LIBOR [Member] \| Interest Rate Caps [Member]
Derivative [Line Items]
Interest rate agreement, notional amount				50,000,000
Interest rate cap agreement, premium				$ 400,000
Interest rate cap agreement, strike price				1.25%
Fixed rate interest rate swap, Maturity date	Mar. 01, 2017