Employee Stock Benefit Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	9 Months Ended
Mar. 31, 2013	Sep. 28, 2013
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		81,230
Shares available for equity grants		404,312
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for equity grants		1,010,720
Range of period in which vested stock expire		10 years
Number of common share granted		470,346
Stock options outstanding		3,283,105
Weighted-average exercise price of stock options		$ 12.26
Aggregate intrinsic value of stock options		$ 3.5
Weighted average remaining contractual term stock options		5 years 2 months 12 days
Stock options outstanding, Exercisable		2,308,726
Weighted-average exercise price of stock options, Exercisable		$ 12.86
Aggregate intrinsic value of stock options, Exercisable		2.8
Weighted average remaining contractual term stock options, Exercisable		3 years 10 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		523,813
Aggregate intrinsic value of stock options		$ 10.5
Restricted stock units outstanding		960,035
Restricted stock units weighted average remaining vesting period		2 years 8 months 12 days
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	158,365
Award measurement period		1 year
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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- Definition

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

-SubTopic 10

-Section 50

-Paragraph 2

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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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- Definition

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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- 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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- 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

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Section 02

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