Share-Based Compensation - Additional Information (Detail) shares in Thousands, $ in Thousands	1 Months Ended	9 Months Ended
May. 31, 2015 Anniversaries shares	Sep. 30, 2015 USD ($) Anniversaries shares
Non-employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	9
Number of anniversaries of the vesting date following the date of grant \| Anniversaries	1
Restricted shares granted to directors have voting rights and vesting description		The restricted shares granted to these directors have voting rights and vest on the earlier of (a) the one year anniversary of the date of grant or (b) immediately prior to the following year's annual stockholders' meeting.
Restricted Stock Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		324
Number of anniversaries of the vesting date following the date of grant \| Anniversaries		4
Shares withheld for taxes		92
Common stock in lieu of taxes \| $		$ 4,230
Restricted Stock Grants [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		315
Vesting period		5 years
Restricted Stock Grants [Member] \| Executive Officers [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting right percentage, Year Five		20.00%
Restricted Stock Grants [Member] \| Executive Officers [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting right percentage, Year Five		20.00%
Restricted Stock Grants [Member] \| Executive Officers [Member] \| Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting right percentage, Year Five		20.00%
Restricted Stock Grants [Member] \| Executive Officers [Member] \| Sharebased Compensation Award Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting right percentage, Year Five		20.00%
Restricted Stock Grants [Member] \| Executive Officers [Member] \| Sharebased Compensation Award Tranche Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting right percentage, Year Five		20.00%

Number of anniversaries of grant date upon which restricted stock units vest.

No definition available.

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- Definition

The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

No definition available.

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

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- Definition

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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

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