Stockholders' Equity - Stock Repurchases, Cash Dividend (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
May 31, 2019	May 31, 2018
Cash Dividends
Cash dividends declared (in dollars per share)	$ 0	$ 0
Cash dividend paid	$ 2,279	$ 2,000
2009 Stock Option Plan
Stock Repurchases
Treasury shares	22,390	18,405
Treasury stock	$ 846	$ 721

Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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