Line Of Credit Facility, Accordion Feature, Maximum Borrowing Capacity

No definition available.

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Namespace Prefix:	ahh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility, Duration Of Extension Option

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Extension Fee Percentage

+ References

No definition available.

+ Details

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

- Definition

Line Of Credit Facility, Number Of Extension Options

+ References

No definition available.

+ Details

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Namespace Prefix:	ahh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- 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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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

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from borrowings to finance the cost of construction.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=ahh_SeniorUnsecuredTermLoanFacilityMember
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Balance Type:
Period Type:

- Details

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- Details

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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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Balance Type:
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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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- Details

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Indebtedness - Additional Information (Details)		1 Months Ended	3 Months Ended
Indebtedness - Additional Information (Details)	Jan. 31, 2019 USD ($) extension	Apr. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Indebtedness
Credit facility, remaining borrowing capacity			$ 0
Revolving Credit Facility
Indebtedness
Interest rate on credit facility as of end of period			2.49%
Term Loan Facility
Indebtedness
Interest rate on credit facility as of end of period			2.44%
Minimum \| Revolving Credit Facility
Indebtedness
Basis points on unused commitment fee			0.15%
Minimum \| Revolving Credit Facility \| LIBOR
Indebtedness
Stated interest rate, basis spread on variable rate			1.30%
Minimum \| Term Loan Facility \| LIBOR
Indebtedness
Stated interest rate, basis spread on variable rate			1.25%
Maximum \| Revolving Credit Facility
Indebtedness
Basis points on unused commitment fee			0.25%
Maximum \| Revolving Credit Facility \| LIBOR
Indebtedness
Stated interest rate, basis spread on variable rate			1.85%
Maximum \| Term Loan Facility \| LIBOR
Indebtedness
Stated interest rate, basis spread on variable rate			1.80%
Construction loans
Indebtedness
Borrowings under construction loans			$ 18,900,000
Construction loans \| Subsequent Event
Indebtedness
Borrowings under construction loans		$ 4,900,000
Operating Partnership \| New Credit Facility
Indebtedness
Aggregate capacity under the credit facility	$ 355,000,000.0
Operating Partnership \| New Credit Facility \| Revolving Credit Facility
Indebtedness
Aggregate capacity under the credit facility	150,000,000.0
Accordion feature maximum borrowing capacity	$ 700,000,000.0
Number of extension options \| extension	2
Duration of extension option	6 months
Extension fee percentage	0.075%
Credit facility, amount outstanding			150,000,000.0	$ 110,000,000.0
Operating Partnership \| New Credit Facility \| Term Loan Facility
Indebtedness
Aggregate capacity under the credit facility	$ 205,000,000.0
Credit facility, amount outstanding			$ 205,000,000.0	$ 205,000,000