Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Feb. 28, 2017	Feb. 29, 2016
Cash flows from operating activities:
Consolidated net income	$ 235,624	$ 270,215
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	14,371	16,919
Unrealized loss (gain) on marketable securities, net	(3,688)	3,896
Deferred income taxes	12,000	24,000
Changes in operating assets and liabilities:
Accounts receivable	961,586	203,357
Other receivables	(1,058)	(7,062)
Prepaid expenses	(146,990)	(23,373)
Prepaid and recoverable income taxes	(156,833)	(4,562)
Accounts and other payables and accrued expenses and other current liabilities	(700,348)	(7,281)
Income taxes payable	(14,810)	(3,877)
Advances from customers	(14,321)	(147,894)
Net cash provided by operating activities	185,533	324,338
Cash flows from investing activities:
Proceeds from maturities of marketable securities	1,509,000	1,493,000
Purchases of marketable securities	(1,243,000)	(1,778,000)
Purchases of equipment and leasehold improvements	(6,144)	(8,857)
Net cash provided by (used in) investing activities	259,856	(293,857)
Cash flows from financing activities:
Distribution to noncontrolling interest	(60,924)	(87,641)
Net cash used in financing activities	(60,924)	(87,641)
Net increase (decrease) in cash and cash equivalents	384,465	(57,160)
Cash and cash equivalents at beginning of period	4,514,157	3,669,790
Cash and cash equivalents at end of period	4,898,622	3,612,630
Supplemental disclosures of cash flow data:
Income taxes paid	$ 348,000	$ 254,000