Earnings per Common Share (Tables)

6 Months Ended

Jun. 30, 2014

Earnings Per Share [Abstract]

Schedule of Computation of Basic and Diluted Earnings per Common Share

The following table sets forth the computation of basic and diluted earnings per common share:

	Three Months Ended June 30,						Six Months Ended June 30,
	2014			2013			2014			2013
(Dollars in millions, except share amounts, in thousands, and per share amounts)
Net income attributable to Koppers	$	1.6		$	14.4		$	3.8		$	25.4
Less: loss from discontinued operations		(0.1	)		(0.1	)		(0.1	)		0.0
Income from continuing operations attributable to Koppers	$	1.7		$	14.5		$	3.9		$	25.4
Weighted average common shares outstanding:
Basic		20,475			20,727			20,430			20,697
Effect of dilutive securities		107			218			154			238
Diluted		20,582			20,945			20,584			20,935
Earnings per common share – continuing operations:
Basic earnings per common share	$	0.08		$	0.70		$	0.19		$	1.23
Diluted earnings per common share		0.08			0.70			0.19			1.21
Other data:
Antidilutive securities excluded from computation of diluted earnings per common share		284			254			258			227