Statement of Changes in Deficit (USD $)	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total Greystone Stockholders Deficit [Member]	Variable Interest Entities [Member]	Total
Beginning Balance, amount at May. 31, 2012	$ 5	$ 2,611	$ 53,089,293	$ (60,586,143)	$ (7,494,234)	$ 1,040,405	$ (6,453,829)
Beginning Balance, shares at May. 31, 2012	50,000	26,111,201	0	0	0	0	0
Cash distributions	0	0	0	0	0	(102,079)	(102,079)
Preferred dividends	0	0	0	(326,781)	(326,781)	0	(326,781)
Net income	0	0	0	2,591,658	2,591,658	201,552	2,793,210
Stock based compensation	0	0	53,424	0	53,424	0	53,424
Ending Balance, amount at May. 31, 2013	5	2,611	53,142,717	(58,321,266)	(5,175,933)	1,139,878	(4,036,055)
Ending Balance, shares at May. 31, 2013	50,000	26,111,201
Cash distributions						(347,318)	(347,318)
Preferred dividends				(325,000)	(325,000)		(325,000)
Net income				2,931,063	2,931,063	200,563	3,131,626
Stock based compensation			53,424		53,424		53,424
Common stock options exercised, amount		35	139,965		140,000		140,000
Common stock options exercised, shares		350,000
Ending Balance, amount at May. 31, 2014	$ 5	$ 2,646	$ 53,336,106	$ (55,715,203)	$ (2,376,446)	$ 993,123	$ (1,383,323)
Ending Balance, shares at May. 31, 2014	50,000	26,461,201