Segment Results (Tables)

6 Months Ended

Jun. 30, 2019

Segment Reporting [Abstract]

Schedule of Net Sales

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2019		2018		2019		2018
Net sales
Mineral Fiber	$	214.1	$	206.7	$	410.8	$	397.4
Architectural Specialties		57.9		41.9		103.3		78.5
Total net sales	$	272.0	$	248.6	$	514.1	$	475.9

Schedule of Segment Operating Income (Loss)

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2019			2018			2019			2018
Segment operating income (loss)
Mineral Fiber	$	79.4		$	59.5		$	127.0		$	103.2
Architectural Specialties		9.5			8.6			18.7			16.9
Unallocated Corporate		(1.7	)		(2.1	)		(3.8	)		(4.5	)
Total consolidated operating income	$	87.2		$	66.0		$	141.9		$	115.6

Reconciliation of Total Consolidated Operating Income to Earnings Before Income Taxes

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2019			2018			2019			2018
Total consolidated operating income	$	87.2		$	66.0		$	141.9		$	115.6
Interest expense		9.5			9.8			19.9			19.0
Other non-operating (income), net		(5.4	)		(9.1	)		(10.9	)		(18.1	)
Earnings from continuing operations before income taxes	$	83.1		$	65.3		$	132.9		$	114.7

Reconciliation of Total Segment Assets to Total Consolidated Assets

	June 30, 2019		December 31, 2018
Segment assets
Mineral Fiber	$	1,122.1	$	1,096.1
Architectural Specialties		153.3		84.7
Unallocated Corporate		337.9		413.2
Total consolidated assets	$	1,613.3	$	1,594.0