v2.4.0.6

Share-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended	1 Months Ended	9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011	Dec. 31, 2011	Jan. 31, 2012 2007 Plan [Member]	Sep. 29, 2012 2007 Plan [Member]	Aug. 07, 2007 2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of options to purchase shares								3,000,000
Vesting period of options							5 years
Expiration period of options							10 years
Common stock shares added to share reserve						1,700,000
Percentage of company's total shares outstanding					3.00%
Company issued shares of common stock as a result of stock option exercises					629,000
Allocated Share-based Compensation Expense	$ 3.2	$ 2.6	$ 11.0	$ 10.2
Aggregated intrinsic value of options outstanding	32.7		32.7
Aggregated intrinsic value of options exercisable	26.3		26.3
Aggregated intrinsic value of options exercised	1.2		2.1
Unrecognized share-based compensation related to unvested options granted	$ 31.2		$ 31.2
Unrecognized share-based compensation related to unvested options granted, term			6 years 6 months
Weighted average remaining contractual term of options exercisable, years			4 years 1 month 6 days

X

- Definition

The increase in the number of shares of common stock reserved for future issuance.

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- Definition

The maximum number of years after grant date, that a share-based payment arrangement is exercisable, before expiring.

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- Definition

Percentage of total shares outstanding at fiscal year end, to calculate the Evergreen provision, in accordance with the 2007 Plan.

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- Definition

Shares reserved future issuance.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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