Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands	12 Months Ended
Apr. 29, 2017 USD ($)
Goodwill
Balance as of April 30, 2016:	$ 8,116
Acquisition, net of cash acquired	55
Foreign currency translation	(359)
Balance as of April 29, 2017:	7,812
Live Events
Goodwill
Balance as of April 30, 2016:	2,304
Acquisition, net of cash acquired	0
Foreign currency translation	(30)
Balance as of April 29, 2017:	2,274
Commerical
Goodwill
Balance as of April 30, 2016:	3,350
Acquisition, net of cash acquired	55
Foreign currency translation	(206)
Balance as of April 29, 2017:	3,199
Transportation
Goodwill
Balance as of April 30, 2016:	75
Acquisition, net of cash acquired	0
Foreign currency translation	(30)
Balance as of April 29, 2017:	45
International
Goodwill
Balance as of April 30, 2016:	2,387
Acquisition, net of cash acquired	0
Foreign currency translation	(93)
Balance as of April 29, 2017:	$ 2,294

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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