Restructuring Plans - (Additional Information) (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Jul. 04, 2021 USD ($)	Jul. 05, 2020 USD ($)	Mar. 31, 2021 USD ($) Employee	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Restructuring Cost and Reserve [Line Items]
Expected remaining cost	$ 4,666
Restructuring and other exit charges	7,832	$ 1,387
Write-off of assets relating to exit activities	2,141	471
Proceeds from disposal of facility	3,268	$ 0
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,326
Exit charges	6,506
Restructuring and other exit charges	7,832
Restructuring costs incurred	2,142
Employee Severance | Energy Systems
Restructuring Cost and Reserve [Line Items]
Restructuring charges	858
Exit charges	(370)
Restructuring and other exit charges	488
Employee Severance | Motive Power
Restructuring Cost and Reserve [Line Items]
Restructuring charges	432
Exit charges	8,101
Restructuring and other exit charges	8,533
Employee Severance | Specialty
Restructuring Cost and Reserve [Line Items]
Restructuring charges	36
Exit charges	(1,225)
Restructuring and other exit charges	(1,189)
Closure of Facility in Hagen, Germany
Restructuring Cost and Reserve [Line Items]
Expected additional restructuring charges			$ 60,000
Estimated number of positions eliminated | Employee			200
Closure of Facility in Hagen, Germany | Cash charges
Restructuring Cost and Reserve [Line Items]
Expected additional restructuring charges			$ 40,000
Closure of Facility in Hagen, Germany | Severance, Cash Charges
Restructuring Cost and Reserve [Line Items]
Expected additional restructuring charges			23,331
Closure of Facility in Hagen, Germany | Non Cash Charges
Restructuring Cost and Reserve [Line Items]
Expected additional restructuring charges			20,000
Closure of Facility in Hagen, Germany | Severance, Non Cash Charges
Restructuring Cost and Reserve [Line Items]
Expected additional restructuring charges			7,946
Closure of Facility in Hagen, Germany | Employee Severance
Restructuring Cost and Reserve [Line Items]
Write-off of assets relating to exit activities	8,471
Closure Of Facility In Targovishte Bulgaria
Restructuring Cost and Reserve [Line Items]
Expected remaining cost					$ 26,000
Restructuring and other exit charges			$ 220	$ 5,123	$ 20,242
Proceeds from disposal of facility	1,489
Gain on disposal of facility	1,225
Closure of Facility in Samudio, Spain
Restructuring Cost and Reserve [Line Items]
Gain on disposal of facility	1,779
Proceeds for sale of certain licenses and assets	740
Richmond Kentucky Battery Formation Area Fire
Restructuring Cost and Reserve [Line Items]
Prepaid Insurance	10,000
Richmond Kentucky Battery Formation Area Fire | Cleanup
Restructuring Cost and Reserve [Line Items]
Restructuring and other exit charges	9,274
Richmond Kentucky Battery Formation Area Fire | Business Interruption
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred	$ 3,700