Debt - Credit Facility - Additional Information (Details) - USD ($)	Oct. 08, 2019	Feb. 20, 2018
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 750,000.0
Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 600,000,000.0
Maturity date	Mar. 31, 2023
Unsecured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 250,000,000.0	$ 150,000,000.0
Basis spread on variable rate		1.35%
Debt instrument facility fee		0.20%
Maturity date	Mar. 31, 2022
Unsecured Debt \| Senior Unsecured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 100,000,000.0	$ 500,000,000.0
Unsecured Debt \| $300 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 350,000,000.0	$ 350,000,000.0
Basis spread on variable rate		1.25%

Debt instrument facility fee.

No definition available.

Name:	akr_DebtInstrumentFacilityFee
Namespace Prefix:	akr_
Data Type:	num:percentItemType
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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
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

+ Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=akr_SeniorUnsecuredCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=akr_ThreeHundredAndFifthMillionTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: