Schedule of Computation of Basic and Diluted Net Income Per Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Earnings Per Share Disclosure [Line Items]
Net income (loss)	$ 1.1us-gaap_NetIncomeLoss	$ (9.3)us-gaap_NetIncomeLoss
Weighted average number of common shares outstanding - basic	117.3	125.4
Stock options and restricted stock units	$ 2.7
Weighted average number of common shares outstanding - diluted	120.0	125.4
Basic net income (loss) per share	$ 0.01us-gaap_EarningsPerShareBasic	$ (0.07)us-gaap_EarningsPerShareBasic
Diluted net income (loss) per share	$ 0.01us-gaap_EarningsPerShareDiluted	$ (0.07)us-gaap_EarningsPerShareDiluted
Anti-dilutive common stock equivalents	0.5	3.1

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of stock options or restrictive stock units (RSUs).

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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