Revenues (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Dec. 28, 2019	Mar. 30, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Deferred revenue	$ 19,516	$ 17,150
Deferred revenue, current	13,635	12,059
Deferred revenue, noncurrent	$ 5,900	$ 5,100
Minimum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Payment term	15 days
Maximum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Payment term	45 days
Tire Road Hazard Warranty [Member] | Minimum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognition, contract term	21 months
Tire Road Hazard Warranty [Member] | Maximum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognition, contract term	36 months