Additional revolving credit facility maximum aggregate principal amount for accordion feature.

No definition available.

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

- Definition

Line of credit facility increase in maximum borrowing capacity.

+ References

No definition available.

+ Details

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Namespace Prefix:	akr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: 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

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

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-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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

- Definition

Amount of cash distribution paid to unit-holder of limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Topic 272
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Cash inflow received as distributions, returns of capital, or sale proceeds from partnership interests held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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Subsequent Events - Additional Information (Details) - USD ($)				9 Months Ended
	Oct. 31, 2019	Oct. 11, 2019	Feb. 20, 2018	Sep. 30, 2019	Oct. 08, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Maximum borrowing capacity			$ 300,000,000.0
Long-term debt, gross				$ 1,664,142,000		$ 1,560,333,000
Subsequent Event \| Fund V
Subsequent Event [Line Items]
Cash distribution paid to investors		$ 6,300,000
Proceeds from limited partnership investments		$ 1,300,000
Unsecured Debt \| Revolving Credit Facility
Subsequent Event [Line Items]
Maximum borrowing capacity			$ 150,000,000.0
Basis spread on variable rate			1.35%
Unsecured Debt \| Senior Unsecured Credit Facility
Subsequent Event [Line Items]
Maximum borrowing capacity			$ 500,000,000.0
Unsecured Debt \| Term Loan
Subsequent Event [Line Items]
Maximum borrowing capacity			$ 350,000,000.0
Unsecured Debt \| Subsequent Event
Subsequent Event [Line Items]
Additional revolving credit facility maximum aggregate principal amount for accordion feature					$ 750,000,000.0
Unsecured Debt \| Subsequent Event \| Revolving Credit Facility
Subsequent Event [Line Items]
Maximum borrowing capacity					250,000,000.0
Increase in maximum borrowing capacity					100,000,000.0
Unsecured Debt \| Subsequent Event \| Senior Unsecured Credit Facility
Subsequent Event [Line Items]
Maximum borrowing capacity					600,000,000.0
Unsecured Debt \| Subsequent Event \| Term Loan
Subsequent Event [Line Items]
Maximum borrowing capacity					$ 350,000,000.0
Mortgages \| LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate				1.75%
Mortgages \| Forecast \| Consolidated and Unconsolidated Properties
Subsequent Event [Line Items]
Borrowings, amount	$ 140,400,000
Mortgages \| Forecast \| Fund V Consolidated Properties \| Landstown Commons
Subsequent Event [Line Items]
Borrowings, amount	$ 60,900,000
Debt instrument, maturity date	Oct. 24, 2024
Mortgages \| Forecast \| Fund V Consolidated Properties \| Landstown Commons \| LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate	1.70%
Mortgages \| Forecast \| Fund V Consolidated Properties \| Lincoln Commons
Subsequent Event [Line Items]
Borrowings, amount	$ 40,800,000
Debt instrument, maturity date	Oct. 24, 2024
Long-term debt, gross	$ 38,800,000
Mortgages \| Forecast \| Fund V Consolidated Properties \| Lincoln Commons \| LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate	1.70%
Mortgages \| Forecast \| Fund V Unconsolidated Properties \| Tri City Plaza
Subsequent Event [Line Items]
Borrowings, amount	$ 38,700,000
Debt instrument, maturity date	Oct. 18, 2024
Long-term debt, gross	$ 25,400,000
Mortgages \| Forecast \| Fund V Unconsolidated Properties \| Tri City Plaza \| LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate	1.90%
Mortgages \| Fixed Rate \| Forecast \| Fund V Consolidated Properties \| Landstown Commons
Subsequent Event [Line Items]
Interest rate, stated percentage	2.949%
Mortgages \| Fixed Rate \| Forecast \| Fund V Consolidated Properties \| Lincoln Commons
Subsequent Event [Line Items]
Interest rate, stated percentage	2.949%
Mortgages \| Fixed Rate \| Forecast \| Fund V Unconsolidated Properties \| Tri City Plaza
Subsequent Event [Line Items]
Interest rate, stated percentage	3.0935%