Business And Basis Of Presentation (Narrative) (Details) $ in Millions		3 Months Ended
	Apr. 01, 2016 entity	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Business And Basis Of Presentation [Line Items]
Separation costs		$ 27.1	$ 4.3
Subsequent Event [Member]
Business And Basis Of Presentation [Line Items]
Common stock split ratio of AFI share to two AWI shares	0.5
Number of independent publicly-traded companies from separation | entity	2
ASU 2015-03 And 2015-15 [Member]
Business And Basis Of Presentation [Line Items]
Reduction to other non-current assets and decrease to long-term debt		$ 4.1		$ 4.7