Consolidated Statements of Stockholders' Equity (USD $) In Millions		Total		Bachman [Member]	Chemsil [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] Bachman [Member]	Additional Paid-In Capital [Member] Chemsil [Member]	Treasury Stock [Member]	Treasury Stock [Member] Bachman [Member]	Treasury Stock [Member] Chemsil [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2010		$ 300.7				$ 0.3	$ 286.3			$ (64.8)			$ 210.5	$ (131.6)
Revision of prior period (Note 2)		0											(16.1)	16.1
Revised beginning balance		300.7				0.3	286.3			(64.8)			194.4	(115.5)
Net income		47.1											47.1
Changes in cumulative translation adjustment		(3.9)												(3.9)
Changes in unrealized gains/(losses) on derivative instruments, net of tax		(0.7)												(0.7)
Treasury stock re-issued		5.7					0.9			4.8
Treasury stock repurchased		(28.1)								(28.1)
Stock option compensation		4.3					4.3
Deferred taxes	[1]	(2.6)	[2]											(2.6)
Amortization of prior service credit, net of tax		(0.9)												(0.9)
Amortization of actuarial net losses, net of tax		2.0												2.0
Actuarial net gains (losses) arising during the year, net of tax		19.5												19.5
Ending Balance at Dec. 31, 2011		343.1				0.3	291.5			(88.1)			241.5	(102.1)
Net income		66.9											66.9
Dividend paid		(46.7)											(46.7)
Changes in cumulative translation adjustment		7.2												7.2
Changes in unrealized gains/(losses) on derivative instruments, net of tax		(0.1)												(0.1)
Treasury stock re-issued		1.0					(3.5)			4.5
Treasury stock repurchased		(1.4)								(1.4)
Stock option compensation		2.1					2.1
Deferred taxes	[2]	0
Fair value of Strata acquisition-related contingently issuable shares		2.0					2.0
Amortization of prior service credit, net of tax		(1.0)												(1.0)
Amortization of actuarial net losses, net of tax		2.4												2.4
Actuarial net gains (losses) arising during the year, net of tax		(58.5)												(58.5)
Ending Balance at Dec. 31, 2012		317.0				0.3	292.1			(85.0)			261.7	(152.1)
Net income		77.8											77.8
Dividend paid		(12.0)											(12.0)
Changes in cumulative translation adjustment		1.2												1.2
Changes in unrealized gains/(losses) on derivative instruments, net of tax		(0.1)												(0.1)
Treasury stock re-issued		4.6					(4.2)			8.8
Treasury stock repurchased		(3.7)								(3.7)
Excess tax benefit from stock based payment arrangements		3.8					3.8
Stock option compensation		2.5					2.5
Deferred taxes	[2]	0
Fair value of acquisition-related consideration				15.0	6.2			10.5	4.1		4.5	2.1
Amortization of prior service credit, net of tax		(1.0)												(1.0)
Amortization of actuarial net losses, net of tax		4.8												4.8
Actuarial net gains (losses) arising during the year, net of tax		(6.7)												(6.7)
Ending Balance at Dec. 31, 2013		$ 409.4				$ 0.3	$ 308.8			$ (73.3)			$ 327.5	$ (153.9)

[1] Impact on deferred taxes of a change in the associated tax rate on the unrecognized actuarial net losses.

[2] Impact on deferred taxes during the year ended December 31, 2011 of a change in the associated tax rate on the unrecognized actuarial net losses.