Segment Results (Schedule Of Segment Operating Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	$ 67.6	$ 77.6	$ 114.6	$ 120.3
Building Products [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	64.7	53.5	124.0	96.8
Resilient Flooring [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	17.7	21.9	24.1	32.6
Wood Flooring [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	2.5	13.8	3.0	16.3
Unallocated Corporate Segment [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	$ (17.3)	$ (11.6)	$ (36.5)	$ (25.4)