Segment Results (Schedule Of Net Sales To External Customers) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Segment Reporting Information [Line Items]
Total net sales to external customers	$ 694.7	$ 734.2	$ 2,006.1	$ 2,100.1
Building Products [Member]
Segment Reporting Information [Line Items]
Total net sales to external customers	325.9	336.0	926.1	947.9
Resilient Flooring [Member]
Segment Reporting Information [Line Items]
Total net sales to external customers	246.4	271.0	727.2	780.4
Wood Flooring [Member]
Segment Reporting Information [Line Items]
Total net sales to external customers	$ 122.4	$ 127.2	$ 352.8	$ 371.8