Note 8 - Accounting for Share-based Compensation - Fair Value of Options Granted (Details) - $ / shares	3 Months Ended	9 Months Ended
Sep. 01, 2018	Sep. 02, 2017	Sep. 01, 2018	Sep. 02, 2017
Expected life (Year)	4 years 273 days	4 years 273 days	4 years 273 days	4 years 273 days
Weighted-average expected volatility	23.36%	23.91%	23.30%	24.84%
Expected volatility	23.36%	23.91%
Risk-free interest rate	2.72%	1.85%		1.89%
Expected dividend yield	1.16%	1.15%	1.14%	1.12%
Weighted-average fair value of grants (in dollars per share)	$ 11.75	$ 10.58	$ 11.38	$ 10.81
Minimum [Member]
Expected volatility			23.18%	23.91%
Risk-free interest rate			2.38%
Maximum [Member]
Expected volatility			23.58%	24.88%
Risk-free interest rate			2.90%

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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.

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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

Weighted average expected volatility rate of share-based compensation awards.

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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