Equity incentive plan (Details) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
	Sep. 04, 2014	Oct. 31, 2014	Apr. 04, 2007	Sep. 10, 1998
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan term	10 years
Vesting term	5 years
Vesting rate	20.00%
No. of Options Outstanding
Options outstanding beginning of period
Options granted during period	246,000	246,000
Options outstanding end of period		246,000
Options expected to vest
Options exercisable at end of period
Exercise Price
Options outstanding beginning of period
Options granted during period	$ 18.45	$ 18.45
Options outstanding end of period		$ 18.45
Estimated fair value of options granted		$ 1.91
Such value was estimated on the grant date using a binomial lattice option pricing model using the following assumptions:
Expected volatility		30.50%
Risk-free interest rate		2.50%
Imputed option life		6 years 9 months 22 days
Expected dividend yield		6.60%
Compensation expense related to stock options		$ 16,000
Unrecognized compensation cost		454,000
Unrecognized compensation cost, recognition period		5 years
Aggregate intrinsic value of options outstanding		$ 12,300
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		220,000
Plan term		10 years