Revenue (Tables)

9 Months Ended

Sep. 30, 2018

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 three and nine months ended September 30, 2018 and 2017:

	Three months ended September 30				Nine months ended September 30
Mineral Fiber	2018		2017		2018		2017
Distributors	$	164.8	$	152.2	$	459.2	$	430.0
Home centers		18.1		18.7		62.6		63.1
Direct customers		15.5		15.9		46.0		47.6
Retailers and other		14.4		12.2		42.4		38.2
Total	$	212.8	$	199.0	$	610.2	$	578.9

Architectural Specialties [Member]

Disaggregation Of Revenue [Line Items]

Schedule of Net Sales by Major Customer Group within Each Segment

	Three months ended September 30				Nine months ended September 30
Architectural Specialties	2018		2017		2018		2017
Distributors	$	34.3	$	28.5	$	96.1	$	79.9
Direct customers		10.8		5.8		26.2		17.9
Retailers and other		2.6		0.6		3.9		2.6
Total	$	47.7	$	34.9	$	126.2	$	100.4