Marketable Securities (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Feb. 28, 2015
Schedule of length of time that available-for-sale securities were in continuous unrealized loss positions
Less Than 12 Months, Fair Value	$ 2,229
Less Than 12 Months, Unrealized Losses	(7)
Greater Than or Equal to 12 Months, Fair Value	1,139
Greater Than or Equal to 12 Months, Unrealized Losses	(111)
Total Fair Value	3,368
Total Unrealized Losses	(118)
Municipal bonds
Schedule of length of time that available-for-sale securities were in continuous unrealized loss positions
Less Than 12 Months, Fair Value	2,229
Less Than 12 Months, Unrealized Losses	(7)
Greater Than or Equal to 12 Months, Fair Value	1,139
Greater Than or Equal to 12 Months, Unrealized Losses	(111)
Total Fair Value	3,368
Total Unrealized Losses	$ (118)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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Amount of unrealized loss on securities classified as available-for-sale.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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