Share repurchases (Details) - USD ($)				12 Months Ended
	Mar. 20, 2015	Sep. 04, 2014	Dec. 17, 2013	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2013	Feb. 17, 2015	Dec. 04, 2013
Share repurchases [Abstract]
Number of shares authorized to repurchase		100,572					100,000	24,400
Number of shares repurchased	94,302		20,400	94,302	120,972
Shares repurchased, value	$ 2,168,946	$ 1,855,553	$ 357,000	$ 2,169,000	$ 2,213,000
Stock repurchased price (per share)	$ 23.00	$ 18.45	$ 17.50