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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	a_EmployeeStockPurchasePlanAbstract
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For an employee stock purchase plan, common stock purchase price ratio for eligible employees.

No definition available.

Name:	a_EmployeeStockPurchasePlanEligibleEmployeeCommonStockPurchasePriceRatio
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Data Type:	num:percentItemType
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Period Type:	duration

Percentage of annual increase in shares authorized for issuance in ESPP automatically, when a Board of Directors does not specifically determine an amount.

No definition available.

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Period Type:	duration

Reflects the duration as to when the share-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, in years, months, quarter of a year).

No definition available.

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Aggregate participant contributions for the number of shares of common stock to be issued to participants excluded from available for issuance balance at the end of period.

No definition available.

Name:	a_ShareBasedCompensationArrangementByShareBasedPaymentAwardEmployeeStockPurchasePlanNumberAggregateParticipantContributions
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Data Type:	xbrli:monetaryItemType
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The maximum number of shares originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the share-based compensation plan. As stock options and equity instruments other than options are awarded to participants, the shares remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

No definition available.

Name:	a_ShareBasedCompensationArrangementByShareBasedPaymentAwardEmployeeStockPurchasePlanNumberOfSharesAuthorized
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

No definition available.

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Data Type:	num:percentItemType
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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vesting Period By Year

No definition available.

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No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

An entity may opt to disclose the percent of market value on offering date that participants pay for options granted.

No definition available.

Name:	a_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncentiveCompensationPlanPercentOfMarketPrice
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The maximum number of shares that can be issued under ESPP.

No definition available.

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

Description of pertinent provisions of share based compensation awards that have actual or potential impact upon the company's financial statements.

No definition available.

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The maximum payout range for participants of the original target grant based upon the company's attainments of pre-established operating ratio targets.

No definition available.

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Data Type:	num:percentItemType
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The minimum payout range for participants of the original target grant based upon the company's attainments of pre-established operating ratio targets.

No definition available.

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Data Type:	num:percentItemType
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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

No definition available.

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Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Percentage of vesting of share-based compensation awards.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
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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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Data Type:	xbrli:sharesItemType
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Number of shares issued during the period as a result of an employee stock purchase plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5