Cash Flow Information - Change in Operating Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
May 02, 2020	Apr. 27, 2019	Apr. 28, 2018
(Increase) decrease:
Account receivable	$ (7,461)	$ 10,856	$ 2,266
Long-term receivables	(1,173)	329	1,548
Inventories	(8,347)	(4,076)	(8,517)
Contract assets	1,931	3,040	(5,911)
Prepaid expenses and other current assets	(1,403)	472	(1,252)
Income taxes receivables	533	4,250	(4,747)
Investment in affiliates and other assets	3,137	(48)	(413)
Increase (decrease):
Accounts payable	2,377	(2,747)	(2,573)
Contract liabilities	4,548	10,774	3,480
Accrued expenses	6,745	4,631	3,472
Warranty obligations	273	(4,393)	346
Long-term warranty obligations	883	(1,079)	1,729
Income taxes payable	390	(3,023)	(592)
Long-term marketing obligations and other payables	(387)	(1,116)	379
Change in operating assets and liabilities	$ (8,090)	$ 11,886	$ 1,863

Increase (Decrease) In Long-Term Warranty Obligation

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- Definition

Increase (Decrease) In Short-Term Warranty Obligation

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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- Definition

The increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid.

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- Definition

Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

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- Definition

The increase (decrease) during the reporting period in income taxes receivable, which represents the amount due from tax authorities for refunds of overpayments or recoveries of income taxes paid.

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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The increase (decrease) during the reporting period in the amount due within one year (or one business cycle) of receivables that were originally due beyond one year (or one business cycle).

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Amount of increase (decrease) in operating assets classified as other.

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Amount of increase (decrease) in operating assets after deduction of operating liabilities classified as other.

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Amount of increase (decrease) in operating liabilities classified as other.

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- Definition

Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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