Segment Results (Schedule Of Segment Operating Income (Loss)) (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 consolidated operating income (loss)	$ 108.6	$ 91.1	$ 228.9	$ 215.9
Building Products [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	81.1	72.4	177.9	191.0
Resilient Flooring [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	25.3	10.6	57.9	20.6
Wood Flooring [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	13.5	17.4	29.8	34.3
Unallocated Corporate (Expense) [Member]
Segment Reporting Information [Line Items]
Total consolidated operating income (loss)	$ (11.3)	$ (9.3)	$ (36.7)	$ (30.0)