Stockholders' Equity (Details 2) (Stock options, USD $)	9 Months Ended
Aug. 31, 2013	Sep. 01, 2012
Other Disclosures
Number of option holders	17
2009 Stock Option Plan
Griffin Stock Option Plan
Expiration term	10 years
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)	40.30%	41.10%
Range of risk free interest rate (as a percent)	1.33%	1.16%
Expected option term	8 years 6 months	8 years 6 months
Annual dividend yield	$ 0.20
2009 Stock Option Plan \| Non-employee directors
Griffin Stock Option Plan
Fair values of stock options granted (in dollars per share)	$ 12.94	$ 11.32
Granted (in shares)	8,112	6,748

The period of time, from the grant date until the time at which the share-based award expires.

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The number of option holders as at the end of the reporting period.

+ References

No definition available.

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- Definition

The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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- Definition

Expected term of share-based compensation awards, 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

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-SubTopic 10

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-Name Staff Accounting Bulletin (SAB)

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-Section D

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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