Employee Stock Benefit Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 28, 2015
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of period in which vested stock expire	10 years
Stock options outstanding	2,268,229
Weighted-average exercise price of stock options	$ 11.31
Aggregate intrinsic value of stock options	$ 3.0
Weighted average remaining contractual term stock options	5 years 2 months 12 days
Stock options outstanding, Exercisable	1,917,729
Weighted-average exercise price of stock options, Exercisable	$ 11.53
Aggregate intrinsic value of stock options, Exercisable	2.6
Weighted average remaining contractual term stock options, Exercisable	4 years 8 months 12 days
Employee Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	1 year
Employee Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	4 years
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of stock options	12.9
Number of common share granted	435,601
Units outstanding	1,169,719
Weighted average remaining vesting period	1 year 10 months 24 days
Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	1 year
Restricted Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	4 years
Equity-Based Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	3 years
Aggregate intrinsic value of stock options	$ 4.5
Units outstanding	404,867
Weighted average remaining vesting period	1 year 9 months 18 days
Award measurement period	1 year
Equity-Based Performance Stock Units [Member] \| Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock units awarded	148,370
Equity-Based Performance Stock Units [Member] \| Senior Executives [Member] \| Vest on Second and Third Anniversary Grant Date [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Rate of shares vest	50.00%
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%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for equity grants	183,591
Percentage of fair value of common stock, common stock price	85.00%
Shares issued under Employee Stock Purchase Plan	0
2005 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for equity grants	591,373

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 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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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Percentage of vesting of share-based compensation awards.

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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.

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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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Period from grant date that an equity-based award expires, 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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- Definition

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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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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- Definition

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 by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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

Purchase price of common stock expressed as a percentage of its fair value.

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- Definition

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

+ References

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- Definition

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

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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