Long-Lived Assets - Goodwill (Details) $ in Thousands	12 Months Ended
Apr. 30, 2016 USD ($)
Goodwill
Balance as of May 2, 2015:	$ 5,269
Acquisition, net of cash acquired	2,715
Foreign currency translation	132
Balance as of April 30, 2016:	8,116
Live Events
Goodwill
Balance as of May 2, 2015:	2,321
Acquisition, net of cash acquired	0
Foreign currency translation	(17)
Balance as of April 30, 2016:	2,304
Commerical
Goodwill
Balance as of May 2, 2015:	721
Acquisition, net of cash acquired	2,502
Foreign currency translation	127
Balance as of April 30, 2016:	3,350
Transportation
Goodwill
Balance as of May 2, 2015:	91
Acquisition, net of cash acquired	0
Foreign currency translation	(16)
Balance as of April 30, 2016:	75
International
Goodwill
Balance as of May 2, 2015:	2,136
Acquisition, net of cash acquired	213
Foreign currency translation	38
Balance as of April 30, 2016:	$ 2,387

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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