Name:	akca_AccruedLiabilityForContributionsToEmployeeStockPurchasePlan
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The annual maximum increase in the number of shares of common stock that may be issued under the Employee Stock Purchase Plan (ESPP), commencing on January 1, 2018 and ending on (and including) January 1, 2027.

No definition available.

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The percentage of the total number of shares outstanding on December 31st of the preceding calendar year used to calculate the annual increase in the number of shares of common stock that may be issued under the Employee Stock Purchase Plan (ESPP), commencing on January 1, 2018 and ending on (and including) January 1, 2027.

No definition available.

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The difference between the maximum number of shares authorized for issuance under the plan (including the effects of amendments and adjustments) and the number of shares already issued under the plan.

No definition available.

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Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
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- References

No definition available.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Gross number of share options (or share units) granted during the period.

No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Number of shares issued during the period as a result of an employee stock purchase plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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