Significant Accounting Policies (Details) - Revenue from contracts with customers - USD ($)	3 Months Ended		9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Disaggregation of Revenue [Line Items]
Revenue From Customers	$ 1,177,000	$ 1,261,000	$ 3,968,000	$ 4,035,000
Clinical Lab [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	723,000	1,043,000	2,769,000	3,150,000
OTC [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	271,000	131,000	778,000	653,000
Physicians' Office [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	32,000	48,000	157,000	142,000
Contract Manufacturing [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	$ 151,000	$ 39,000	$ 264,000	$ 90,000