Represents the optional maximum extension term for ground leases.

No definition available.

Name:	ahh_MaximumOptionalGroundLeaseExtensionTerm
Namespace Prefix:	ahh_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of ground leases.

+ References

No definition available.

+ Details

Name:	ahh_NumberOfGroundLeases
Namespace Prefix:	ahh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Property Occupancy Rate

+ References

No definition available.

+ Details

Name:	ahh_PropertyOccupancyRate
Namespace Prefix:	ahh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

No definition available.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of separate real estate development properties located on land subject to ground leases.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfPropertiesSubjectToGroundLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

+ Details

Name:	us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=ahh_RentalRevenueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=ahh_HamptonsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=ahh_TownCenterPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=ahh_RichmondTowerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=ahh_WilliamsMullenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=ahh_GeneralContractingAndRealEstateServicesRevenuesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=ahh_BaltimoreMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=ahh_GeneralContractingAndRealEstateServicesSegmentProfitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ahh_OperatingPartnershipMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Commitments and Contingencies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) property item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Commitments and Contingencies
Line of credit, performance and payment bonds	$ 183.0	$ 192.2
Ground rent expense	$ 1.7	$ 1.8	$ 1.5
Number of ground leases \| item	5
Number of properties subject to ground leases \| property	4
Maximum optional ground lease extension term	40 years
Minimum
Commitments and Contingencies
Lease term	20 years
Maximum
Commitments and Contingencies
Lease term	65 years
Rental Revenues [Member] \| Hampton Roads Properties [Member]
Commitments and Contingencies
Concentrations of Credit Risk	68.00%	69.00%	70.00%
Rental Revenues [Member] \| Town Center Properties [Member]
Commitments and Contingencies
Concentrations of Credit Risk	46.00%	47.00%	48.00%
Rental Revenues [Member] \| Richmond Tower
Commitments and Contingencies
Concentrations of Credit Risk	11.00%	13.00%	15.00%
Rental Revenues [Member] \| Minimum \| Williams Mullen [Member]
Commitments and Contingencies
Area of Richmond Tower occupied	80.00%
General Contracting and Real Estate Services Revenues [Member] \| Baltimore [Member]
Commitments and Contingencies
Concentrations of Credit Risk	64.00%	41.00%
General Contracting and Real Estate Services Segment Profit [Member] \| Baltimore [Member]
Commitments and Contingencies
Concentrations of Credit Risk	50.00%	27.00%
Operating Partnership
Commitments and Contingencies
Outstanding letters of credit	$ 8.0	$ 8.5