Financial Instruments (Details 2) $ in Thousands	Aug. 31, 2019 USD ($)
Amortized Cost
Due within one year	$ 251
Due after one year through five years	9,124
Due after five years through 10 years	2,015
Due after 10 years through 15 years	0
Due beyond 15 years	406
Total	11,796
Estimated Fair Value
Due within one year	251
Due after one year through five years	9,289
Due after five years through 10 years	2,037
Due after 10 years through 15 years	0
Due beyond 15 years	408
Total	$ 11,985