The incremental compensation expense incurred in connection with the settlement, modification or cancellation of outstanding stock-based compensation awards pursuant to the August 9, 2013 Merger transaction.

No definition available.

+ Details

Name:	am_PostMergerIncrementalCompensationExpense
Namespace Prefix:	am_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

+ Details

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

- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.4)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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

- Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=am_MergerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
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Merger - Charges Incurred Associated with Merger (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2013
Restructuring Cost and Reserve [Line Items]
Incremental compensation expense		$ 10,601
Total	289,433us-gaap_GeneralAndAdministrativeExpense	297,443us-gaap_GeneralAndAdministrativeExpense	298,569us-gaap_GeneralAndAdministrativeExpense
Merger [Member]
Restructuring Cost and Reserve [Line Items]
Total		28,125
Administrative and General Expenses [Member] \| Merger [Member]
Restructuring Cost and Reserve [Line Items]
Incremental compensation expense		10,601
Transaction-related costs		$ 17,524