Stockholders' Equity - Noncontrolling Interests (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Oct. 02, 2016	Sep. 27, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 5,304
Net earnings attributable to noncontrolling interests	$ 2,843	$ 257	2,797	$ 710
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount	(108)	(1,584)	(663)	(589)
Amount reclassified out of AOCI, net of tax	268	315	549	638
Total other comprehensive (loss) income, net of tax	3,198	(32,331)	(19,191)	(12,454)
Total comprehensive income	45,991	$ 7,437	68,221	75,248
Dividends paid to stockholders			(15,200)	(15,553)
Option proceeds			5	$ 63
Ending balance	$ 5,133		$ 5,133
Dividends declared (in dollars per share)	$ 0.175	$ 0.175	$ 0.35	$ 0.35
Equity Attributable to EnerSys Stockholders
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 1,013,131
Net earnings attributable to noncontrolling interests			90,209
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount			2,428
Amount reclassified out of AOCI, net of tax			549
Foreign currency translation adjustment, Net-of Tax Amount			(21,974)
Total other comprehensive (loss) income, net of tax			(18,997)
Total comprehensive income			71,212
Dividends paid to stockholders			(15,200)
Option proceeds			1,742
Ending balance	$ 1,070,885		1,070,885
Nonredeemable Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			5,304
Net earnings attributable to noncontrolling interests			85
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount			0
Amount reclassified out of AOCI, net of tax			0
Foreign currency translation adjustment, Net-of Tax Amount			(256)
Total other comprehensive (loss) income, net of tax			(256)
Total comprehensive income			(171)
Dividends paid to stockholders			0
Option proceeds			0
Ending balance	5,133		5,133
Total Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			1,018,435
Net earnings attributable to noncontrolling interests			90,294
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount			2,428
Amount reclassified out of AOCI, net of tax			549
Foreign currency translation adjustment, Net-of Tax Amount			(22,230)
Total other comprehensive (loss) income, net of tax			(19,253)
Total comprehensive income			71,041
Dividends paid to stockholders			(15,200)
Option proceeds			1,742
Ending balance	$ 1,076,018		$ 1,076,018