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Share Incentive and Other Compensation - Additional Information (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unit based compensation |  |  | $ 5,442,000 | $ 6,113,000 |  |
Trustee fees |  |  | 700,000 | 600,000 |  |
Total unrecognized compensation cost related to nonvested awards | $ 20,500,000 |  | $ 20,500,000 |  |  |
Weighted-average period over which cost is expected to be recognized |  |  | 1 year 10 months 24 days |  |  |
Performance Period Ending December 31, 2021 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 33.30% |  |  |
Award vesting period |  |  | 3 years |  |  |
LTIP Units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total fair value of shares that vested |  |  | $ 8,500,000 |  | $ 12,800,000 |
LTIP Units | Trustee |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 18,009 |  |  |
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date | 6,463 |  | 6,463 |  |  |
LTIP Units | Performance Period Ending December 31, 2021 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 66.70% |  |  |
Award vesting period |  |  | 3 years |  |  |
LTIP Units | Tranche One | Trustee |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 11,546 |  |  |
Restricted shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total fair value of shares that vested |  |  | $ 600,000 |  | $ 800,000 |
Restricted shares | Trustee |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 17,318 |  |  |
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date | 3,996 |  | 3,996 |  |  |
Restricted shares | Tranche One | Trustee |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 13,322 |  |  |
LTIP Units and Restricted Stock |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total value of restricted shares and LTIP units as of the grant date | $ 11,100,000 |  |  |  |  |
Weighted average grant date fair value, grants (in dollars per share) |  |  | $ 32.50 |  | $ 26.64 |
LTIP Units and Restricted Stock | Trustee |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  |  | 3 years |  |  |
Annual vesting rate of shares granted to trustees that begin vesting on the second anniversary of grant date |  |  | 33.00% |  |  |
LTIP Units and Restricted Stock | General and Administrative Expense |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unit based compensation | $ 1,800,000 | $ 2,200,000 | $ 3,700,000 | 4,300,000 |  |
LTIP Units and Restricted Stock | Performance Period Ending December 31, 2021 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  |  | 3 years |  |  |
LTIP Units and Restricted Stock | Performance Fails To Achieve, Earned Performance-Based Shares Vest At End Of Performance Period |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 60.00% |  |  |
LTIP Units and Restricted Stock | Performance Fails To Achieve |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 40.00% |  |  |
Award vesting period |  |  | 2 years |  |  |
LTIP Units and Restricted Stock | Minimum | TSR percentile falls between the 25th percentile and the 50th percentile |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 50.00% |  |  |
LTIP Units and Restricted Stock | Minimum | TSR percentile falls between the 50th percentile and 75th percentile |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 100.00% |  |  |
LTIP Units and Restricted Stock | Maximum | TSR percentile falls between the 25th percentile and the 50th percentile |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 100.00% |  |  |
LTIP Units and Restricted Stock | Maximum | TSR percentile falls between the 50th percentile and 75th percentile |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting percentage |  |  | 200.00% |  |  |
Employee Benefit Plans |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense |  |  | $ 200,000 | 200,000 |  |
Share Incentive Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | 692,409 |  | 692,409 |  |  |
Share Incentive Plan | LTIP Units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 330,718 |  |  |
Share Incentive Plan | Restricted shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  |  | 8,041 |  |  |
Performance Shares 2018 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Performance period |  |  | 3 years |  |  |
Volatility rate |  |  | (19.60%) |  |  |
Risk-free interest rates |  |  | (2.50%) |  |  |
Long Term Investment Alignment Program |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Max percentage of future fund III promote that may be awarded to senior executives |  |  |  |  |  | 25.00%
Long Term Investment Alignment Program | Fund III |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of promote awarded as share based compensation award |  |  |  |  |  | 25.00%
Compensation expense |  |  | $ 0 | 0 |  |
Long Term Investment Alignment Program | Fund IV |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of promote awarded as share based compensation award |  |  |  |  |  | 22.80%
Awards in connection with fund to have intrinsic value | $ 0 |  | 0 |  |  |
Compensation expense |  |  | 0 | 0 |  |
Long Term Investment Alignment Program | Fund V |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of promote awarded as share based compensation award |  |  |  |  |  | 2.20%
Awards in connection with fund to have intrinsic value | $ 0 |  | 0 |  |  |
Compensation expense |  |  | $ 0 | $ 0 |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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Name: | srt_ConsolidatedEntitiesAxis=akr_FundVMember
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Data Type: | na
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