Employee Stock Benefit Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 30, 2013	Mar. 30, 2012
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair value of common stock, common stock price	85.00%
Shares issued under Employee Stock Purchase Plan	0
Shares available for equity grants	485,542
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for equity grants	1,000,825
Range of period in which vested stock expire	10 years
Number of common share granted	445,346
Stock options outstanding	3,435,701
Weighted-average exercise price of stock options	12.21
Aggregate intrinsic value of stock options	1.8
Weighted average remaining contractual term stock options	5 years 9 months 18 days
Stock options outstanding, Exercisable	2,454,448
Weighted-average exercise price of stock options, Exercisable	12.76
Aggregate intrinsic value of stock options, Exercisable	1.8
Weighted average remaining contractual term stock options, Exercisable	4 years 4 months 24 days
Employee Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum period in which vested stock become exercisable	1 year
Employee Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum period in which vested stock become exercisable	4 years
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common share granted	474,313
Aggregate intrinsic value of stock options	9.3
Restricted stock units outstanding	991,267
Restricted stock units weighted average remaining vesting period	2 years
Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum period in which vested stock become exercisable	1 year
Restricted Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum period in which vested stock become exercisable	4 years
Equity-Based Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum period in which vested stock become exercisable	3 years
Number of common share granted	140,865	128,916
Award measurement period	1 year
Common stock issued on achievement of performance goals	77,455
Equity-Based Performance Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted on achievement of performance goals	0.00%
Equity-Based Performance Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted on achievement of performance goals	150.00%

Percentage of the Fair Value to Determine the price of common stock.

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Share based compensation arrangement by share based payment award award measurement period.

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Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Term

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Share based compensation arrangement by share based payment award percentage of shares available for issue.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 505

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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