Basis of Presentation (Tables)	3 Months Ended
May 25, 2012
Basis of Presentation [Abstract]
Schedule of charges with no comparative amounts in prior year	Schedule of charges with no comparative amounts in prior year
Charges reflected in the reportable segment	Charges reflected in the reportable segment

Schedule of activities and transactions associated related cost.

No definition available.

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Namespace Prefix:	am_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration