Equity incentive plan (Details) - USD ($)					12 Months Ended
	Nov. 10, 2016	Sep. 04, 2014	Apr. 04, 2004	Sep. 10, 1998	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to be issued under plan				920,000
Increase in number of shares authorized			300,000	920,000
Shares available for issuance					185,020
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan term	10 years	10 years
Vesting term	5 years	5 years
No. of Options Outstanding
Options outstanding beginning of period					229,880
Options exercised during period					38,000
Options granted during period	38,000	246,000
Options forfeited/cancelled during period					(100)
Options outstanding end of period					267,780	229,880
Options vested and expected to vest					262,280
Options exercisable at end of period					140,260
Exercise Price
Options outstanding beginning of period					$ 18.45
Options exercised during period					21.00
Options granted during period	$ 21.00	$ 18.45
Options forfeited/cancelled during period					18.45
Options outstanding end of period					18.81	$ 18.45
Estimated fair value of options granted					$ 3.54
Such value was estimated on the grant date using a binomial lattice option pricing model using the following assumptions:
Expected volatility					30.30%
Risk-free interest rate					2.23%
Imputed option life					6 years 3 months 19 days
Expected dividend yield					4.66%
Compensation expense related to stock options					$ 122,000	$ 94,000	$ 94,000
Unrecognized compensation cost					$ 279,000
Unrecognized compensation cost, recognition period					2 years 4 months 24 days
Aggregate intrinsic value of options expected to vest					$ 78,000
Aggregate intrinsic value of options exercisable					$ 46,000