Net Earnings (Loss) Per Share (Narrative) (Details) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Earnings (Net Loss) Per Share [Abstract]
Potentially dilutive securities	0.7	1.7	1.3	1.9

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would have been antidilutive for the period presented.

No definition available.

Name:	amwd_EarningsPerSharePotentiallyDilutiveSecurities1
Namespace Prefix:	amwd_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration