Certificates of Deposit and Marketable Securities (Details) - USD ($)	Feb. 29, 2016	May. 31, 2015
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	$ 1,552,672	$ 1,271,568
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	1,529,000	1,244,000
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	23,672	27,568
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	$ 23,672	$ 27,568
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	$ 23,672	$ 27,568
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Summary of assets measured at fair value on recurring basis
Assets measured at fair value, Total	1,529,000	1,244,000
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	$ 1,529,000	$ 1,244,000
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