Revenue (Tables)

12 Months Ended

Dec. 31, 2020

Mineral Fiber [Member]

Disaggregation Of Revenue [Line Items]

Schedule of Net Sales by Major Customer Group within Each Segment

The following tables provide net sales by major customer group within the Mineral Fiber and Architectural Specialties segments for the years ended December 31, 2020, 2019 and 2018:

Mineral Fiber	2020		2019		2018
Distributors	$	525.2	$	622.9	$	601.4
Home centers		96.1		85.2		84.0
Direct customers		54.3		61.2		60.3
Retailers and other		50.4		57.3		55.9
Total	$	726.0	$	826.6	$	801.6

Architectural Specialties [Member]

Disaggregation Of Revenue [Line Items]

Schedule of Net Sales by Major Customer Group within Each Segment

Architectural Specialties	2020		2019		2018
Distributors	$	135.5	$	138.3	$	129.8
Direct customers		73.3		68.0		36.7
Retailers and other		2.1		5.2		7.2
Total	$	210.9	$	211.5	$	173.7