Quarterly report pursuant to Section 13 or 15(d)

Description of Business and Significant Accounting Policies - Summary of Option Activity (Details)

v2.4.1.9
Description of Business and Significant Accounting Policies - Summary of Option Activity (Details) (USD $)
 1 Months Ended 6 Months Ended
Jun. 30, 2008
Oct. 31, 2014
Summary of option activity, Shares    
Balance April 30, 2014   264,244us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Granted 8,333us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross  
Expired   (16,000)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod
Balance October 31, 2014   248,244us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Exercisable October 31, 2014   235,744us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber
Expected to vest October 31, 2014   224,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber
Summary of option activity, Weighted average exercise price    
Balance April 30, 2014   $ 12.42us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Expired   $ 15.42us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice
Balance October 31, 2014   $ 12.23us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Exercisable October 31, 2014   $ 12.75us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
Expected to vest October 31, 2014   $ 12.23us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice
Summary of option activity, Additional disclosures    
Balance, Weighted average remaining contractual life   4 years 3 months [1]
Exercisable October 31, 2014, Weighted average remaining contractual life   4 years [1]
Expected to vest October 31, 2014, Weighted average remaining contractual life   4 years [1]
Balance April 30, 2014, Aggregate intrinsic value   $ 14,750us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
Balance October 31, 2014, Aggregate intrinsic value   14,750us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
Exercisable October 31, 2014, Aggregate intrinsic value   7,375us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1
Expected to vest October 31, 2014, Aggregate intrinsic value   $ 7,375us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue
[1] This amount represents the weighted average remaining contractual life of stock options in years.