Share-Based Employee Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
May 31, 2014	May 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares authorized under the Plan	9,600,000
Shares available for grant under the Plan	2,800,000
Stock options, issued	0
Stock options, expired or forfeited	0
Stock options, exercised	60,000
Restricted stock, issued	155,300
Restricted stock, vested	6,692
Restricted stock, forfeited	6,300
Share-based Compensation	$ 1.2	$ 1.1
Unrecognized compensation cost related to non-vested share-based compensation arrangements	3.4
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options	0.3
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement By Share-based Payment Award, Options Outstanding, Contractual Term	10 years
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	$ 1.2	$ 1.1

Share-based Compensation Arrangement By Share-based Payment Award, Options Outstanding, Contractual Term

No definition available.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (j)

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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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

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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