Certificates of Deposit and Marketable Securities (Details) - USD ($)	Nov. 30, 2016	May 31, 2016
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	$ 1,538,760	$ 1,553,272
Fair Value, Measurements, Recurring [Member] | Certificates of Deposit [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	1,511,000	1,528,000
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	27,760	25,272
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	27,760	25,272
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Certificates of Deposit [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Equity Securities [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	27,760	25,272
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	1,511,000	1,528,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Certificates of Deposit [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	1,511,000	1,528,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Equity Securities [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Certificates of Deposit [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Equity Securities [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total