Reconciliation of Net Income (Loss) to Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Income from continuing operations	$ 10.4	$ 14.4
Gain from discontinued operations and disposal, net of tax	3.2	0.5
Net income	$ 13.6	$ 14.9
Weighted average shares outstanding - Basic (shares)	62.1	62.7
Dilutive effect of common stock equivalents (shares)	0.9	1.0
Weighted average shares outstanding - Diluted (shares)	63.0	63.7
Basic earnings per share:
Earnings from continuing operations (usd per share)	$ 0.17	$ 0.23
Gain from discontinued operations and disposal, net of tax (usd per share)	0.05	0.01
Net earnings per share (usd per share)	0.22	0.24
Diluted earnings per share:
Earnings from continuing operations (usd per share)	0.17	0.22
Gain from discontinued operations and disposal, net of tax (usd per share)	0.05	0.01
Net earnings per share (usd per share)	$ 0.22	$ 0.23

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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