Annual report pursuant to Section 13 and 15(d)

Relationship with AWI - Additional Information (Details)

v3.8.0.1
Relationship with AWI - Additional Information (Details) - Armstrong World Industries - Allocation of corporate and other expenses - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Related Party Transaction [Line Items]      
Expenses from transactions with related party $ 0.0 $ 0.8 $ 47.8
Cost of goods sold      
Related Party Transaction [Line Items]      
Expenses from transactions with related party   0.0 10.0
Selling, general and administrative expenses      
Related Party Transaction [Line Items]      
Expenses from transactions with related party   0.5 34.3
Other expense, net      
Related Party Transaction [Line Items]      
Expenses from transactions with related party   $ 0.3 $ 3.5