Acquisitions - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	6 Months Ended	0 Months Ended	3 Months Ended
	Aug. 14, 2013	Oct. 31, 2013	Oct. 31, 2013	May 30, 2014	Jul. 31, 2014	Jan. 31, 2015	Apr. 30, 2014
Business Acquisition [Line Items]
Business acquisition, purchase price allocate to goodwill						$ 18,749,000	$ 13,819,000
Taylor Manufacturing Systems, USA, LLC
Business Acquisition [Line Items]
Business acquisition, purchase price paid in cash	1,191,000
Business acquisition costs incurred		68,500	68,500
Business acquisition, purchase price allocate to goodwill	1,218,000
Business acquisition, purchase price	1,841,000
Business acquisition, additional cash payments payable in each of three years following closing	200,000
Business acquisition, additional cash payments payable in first anniversary	200,000
Business acquisition, additional cash payments payable in second and third anniversaries	366,000
Business acquisition, cash payments payable in second anniversary						200,000
Business acquisition, cash payments payable in third anniversaries						183,000
Taylor Manufacturing Systems, USA, LLC | Current Technology
Business Acquisition [Line Items]
Remaining estimated economic life of the product	4 years
MID Retail, Inc.
Business Acquisition [Line Items]
Percentage of issued and outstanding shares of capital stock				100.00%
Business acquisition, purchase price paid in cash				8,507,000
Business acquisition, working capital adjustment				678,000
Earnout period				24 months
Additional consideration payments, percentage of license fee revenues				15.00%
Additional consideration payments				1,500,000
Business acquisition costs incurred					66,800
Business acquisition, purchase price allocate to goodwill				$ 4,930,000
MID Retail, Inc. | Current Technology
Business Acquisition [Line Items]
Remaining estimated economic life of the product				3 years