Severances And Related Costs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013 Resilient Flooring [Member]	Mar. 31, 2013 Europe [Member] Resilient Flooring [Member] employee	Mar. 31, 2013 Europe [Member] Resilient Flooring [Member] Cost Of Goods Sold [Member]	Mar. 31, 2013 Europe [Member] Resilient Flooring [Member] SG&A Expense [Member]	Jun. 30, 2012 Europe [Member] Building Products [Member] employee	Jun. 30, 2012 Europe [Member] Building Products [Member] Cost Of Goods Sold [Member]	Jun. 30, 2012 Europe [Member] Building Products [Member] SG&A Expense [Member]	Mar. 31, 2013 Pacific Rim [Member] Resilient Flooring [Member] employee	Mar. 31, 2013 Pacific Rim [Member] Resilient Flooring [Member] Cost Of Goods Sold [Member]
Schedule Of Severances And Related Costs [Line Items]
Severance and related costs	$ 5.2		$ 1.8	$ 1.0	$ 3.4	$ 0.2	$ 3.2		$ 2.4
Positions eliminated		40			35			40

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated not related to a restructuring initiatives, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

No definition available.

Name:	awi_SeveranceAndRelatedCosts
Namespace Prefix:	awi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration