Basic and Diluted (Loss) Earnings Per Common Share - Components of Basic and Diluted Earnings Per Share (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Numerator:
Income from continuing operations	$ 46.5	[1],[2],[3]	$ (15.0)	[1],[2],[3]	$ 10.7	[1],[2],[3]	$ 8.5	[1],[2],[3]	$ 36.4	[4]	$ 0.1	[4]	$ 5.9	[4]	$ 10.4	[4]	$ 50.7	[5]	$ 52.8	[6]	$ 327.0	[7]
Income from discontinued operations					0.4								0.6				0.4	[5]	0.6	[6]	0.3	[7]
Net income	$ 46.5	[1],[2],[3]	$ (15.0)	[1],[2],[3]	$ 11.1	[1],[2],[3]	$ 8.5	[1],[2],[3]	$ 36.4	[3]	$ 0.1	[3]	$ 6.5	[3]	$ 10.4	[3]	$ 51.1	[5]	$ 53.4	[6]	$ 327.3	[7]
Denominator:
Weighted average common shares outstanding - Basic																	52,348,636	[5]	52,173,906	[6]	51,892,824	[7]
Effect of dilutive restricted stock																	8,246	[5]	157,901	[6]	409,812	[7]
Weighted average common shares outstanding - Diluted																	52,356,882	[5]	52,331,807	[6]	52,302,636	[7]
Basic earnings per share:
Continuing operations	$ 0.89		$ (0.29)		$ 0.20		$ 0.16		$ 0.70				$ 0.11		$ 0.20		$ 0.97	[5]	$ 1.01	[6]	$ 6.30	[7]
Discontinued operations					$ 0.01								$ 0.01				$ 0.01	[5]	$ 0.01	[6]	$ 0.01	[7]
Net income	$ 0.89		$ (0.29)		$ 0.21		$ 0.16		$ 0.70				$ 0.12		$ 0.20		$ 0.98	[5]	$ 1.02	[6]	$ 6.31	[7]
Diluted earnings per share:
Continuing operations	$ 0.89		$ (0.29)		$ 0.20		$ 0.16		$ 0.70				$ 0.11		$ 0.20		$ 0.97	[5]	$ 1.01	[6]	$ 6.25	[7]
Discontinued operations					$ 0.01								$ 0.01				$ 0.01	[5]	$ 0.01	[6]	$ 0.01	[7]
Net income	$ 0.89		$ (0.29)		$ 0.21		$ 0.16		$ 0.70				$ 0.12		$ 0.20		$ 0.98	[5]	$ 1.02	[6]	$ 6.26	[7]

[1] Loss from continuing operations, net loss and basic and diluted loss per share for the third quarter of 2012 were unfavorably impacted by $24.1 million in restructuring and related charges recorded as a result of the September 2012 Program and an additional $2.2 million loss contingency recognized related to litigation associated with the Company's 2009 Exchange Offer. (See Note 3, "Restructuring Charges" and Note 19, "Commitments and Contingencies").

[2] Income from continuing operations, net income and basic and diluted earnings per share for the second quarter of 2012 were unfavorably impacted by a $6.7 million loss contingency recognized related to litigation associated with the Company's 2009 Exchange Offer. (See Note 19, "Commitments and Contingencies").

[3] Income from continuing operations, net income and basic and diluted earnings per share for the fourth quarter of 2012 were favorably impacted by an increase in net income driven by a non-cash benefit of $15.8 million related to the reduction of the Company's deferred tax valuation allowance on its net deferred tax assets for certain jurisdictions in the U.S. at December 31, 2012, as a result of the Company's improved earnings trends and cumulative taxable income in those jurisdictions, which is reflected in the provision for income taxes (See Note 13, "Income Taxes").

[4] Income from continuing operations, net income and basic and diluted earnings per share for the fourth quarter of 2011 were favorably impacted by an increase in net income driven by a non-cash benefit of $16.9 million related to the reduction of the Company's deferred tax valuation allowance on its net deferred tax assets for certain jurisdictions outside the U.S. at December 31, 2011 as a result of the Company's improved earnings trends and cumulative taxable income in those jurisdictions. (See Note 13, "Income Taxes").

[5] Basic and diluted earnings per share for the year ended December 31, 2012 were unfavorably impacted by $24.1 million in restructuring and related charges recorded as a result of the September 2012 Program and a $8.9 million loss contingency recognized related to litigation associated with the Company's 2009 Exchange Offer, offset in part by a non-cash benefit of $15.8 million related to the reduction of the Company's deferred tax valuation allowance on its net deferred tax assets for certain jurisdictions in the U.S. at December 31, 2012, as a result of the Company's improved earnings trends and cumulative taxable income in those jurisdictions, which is reflected in the provision for income taxes (See Note 13, "Income Taxes").

[6] Basic and diluted earnings per share for the year ended December 31, 2011 were favorably impacted by an increase in net income driven by a non-cash benefit of $16.9 million related to the reduction of the Company's deferred tax valuation allowance on its net deferred tax assets for certain jurisdictions outside the U.S. at December 31, 2011 as a result of the Company's improved earnings trends and cumulative taxable income in those jurisdictions (See Note 13, "Income Taxes").

[7] Basic and diluted earnings per share for the year ended December 31, 2010 were favorably impacted by an increase in net income driven by a non-cash benefit of $260.6 million related to the Company's net U.S. deferred tax assets at December 31, 2010, recognized through a reduction in the Company's deferred tax valuation allowances as a result of the Company achieving three cumulative years, as well as three consecutive years, of positive U.S. GAAP pre-tax income and taxable income in the U.S., and based upon the Company's then-current expectations for realization of such deferred tax benefits in the U.S. (See Note 13, "Income Taxes").