Marketable Securities (Details) - USD ($) $ in Thousands	May 31, 2017	Aug. 31, 2016
Short-term:
D.N.A (see b below)	$ 1,092	$ 701
Held to maturity bonds (see c below)	1,980	2,154
Marketable securities	3,072	2,855
Long-term:
Held to maturity bonds (see c below)	$ 1,409	$ 530

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle.

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