Consolidated Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Dec. 31, 2017	Jan. 01, 2017
Income Statement [Abstract]
Net sales	$ 658,935	$ 563,697	$ 1,898,849	$ 1,740,348
Cost of goods sold	491,970	408,315	1,408,913	1,254,678
Inventory adjustment relating to exit activities	0	(502)	0	2,157
Gross profit	166,965	155,884	489,936	483,513
Operating expenses	96,717	85,014	283,478	277,512
Restructuring charges and other exit charges (credits)	1,808	(1,153)	4,417	5,037
Legal proceedings charge	0	17,000	0	17,000
Operating earnings	68,440	55,023	202,041	183,964
Interest expense	6,469	5,646	18,712	16,820
Other (income) expense, net	(557)	(1,247)	4,736	(496)
Earnings before income taxes	62,528	50,624	178,593	167,640
Income tax expense	88,307	13,529	112,899	43,133
Net (loss) earnings	(25,779)	37,095	65,694	124,507
Net earnings attributable to noncontrolling interests	68	860	118	(1,937)
Net (loss) earnings attributable to EnerSys stockholders	$ (25,847)	$ 36,235	$ 65,576	$ 126,444
Net (loss) earnings per common share attributable to EnerSys stockholders:
Basic earnings (loss) per common share attributable to EnerSys stockholders (in dollars per share)	$ (0.61)	$ 0.83	$ 1.53	$ 2.92
Diluted earnings (loss) per common share attributable to EnerSys stockholders (in dollars per share)	(0.61)	0.82	1.51	2.88
Dividends per common share (in dollars per share)	$ 0.175	$ 0.175	$ 0.525	$ 0.525
Weighted average shares of common stock outstanding:
Basic weighted-average number of common shares outstanding (in shares)	42,125,745	43,429,525	42,837,986	43,375,474
Diluted weighted-average number of common shares outstanding (in shares)	42,125,745	44,049,674	43,345,926	43,943,010