Commitments and contingencies (Details) - USD ($)	Dec. 29, 2016	Jul. 31, 2015	Aug. 11, 2014
Commitments and contingencies details
Mentor obtained a judgment in the amount against Bhang Corporation and its predecessor in interest	$ 1,921,534.62
Mentor filed suit against Bhang and its owners in the United States District Court for the Northern District of California for co-operative funding agreement with Bhang, seeking return of the investment			$ 1,500,000
The judgment accrues interest at the rate	10.00%
As part of the judgment Bhang owners, Scott Van Rixel and Richard Sellers, who together purchased shares	117,000
Bhang Agreement have the option to return all or part of those shares in exchange for payment of the original purchase price of $1.95 per share plus a pro-rata amount.	58,568.92
Mentor was served with a complaint in an action in the United States District Court for the District of Utah initiated by the wife and daughter of Bhang's corporate counsel related to shares		$ 75,000