v3.7.0.1
Stockholders Equity and Noncontrolling Interests Reclassification from Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2017
Jan. 01, 2017
Oct. 02, 2016
Jul. 03, 2016
Mar. 31, 2016
Dec. 27, 2015
Sep. 27, 2015
Jun. 28, 2015
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2015
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]                      
Cost of goods sold                 $ 1,714,367 $ 1,704,472 $ 1,864,601
Income tax expense                 54,472 50,113 67,814
Net earnings attributable to EnerSys stockholders $ (33,770) $ (36,235) $ (45,636) $ (44,573) $ (9,260) $ (38,478) $ (40,025) $ (48,387) (160,214) (136,150) (181,188)
Net unrealized gain (loss) on derivative instruments | Reclassification out of Accumulated Other Comprehensive Income                      
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]                      
Cost of goods sold                 (6,236) 7,144 2,961
Income tax expense                 2,300 (2,634) (1,092)
Net earnings attributable to EnerSys stockholders                 (3,936) 4,510 1,869
Pension funded status adjustment | Reclassification out of Accumulated Other Comprehensive Income                      
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]                      
Prior service costs and deferrals                 1,431 2,043 1,007
Income tax expense                 (466) (483) (260)
Net earnings attributable to EnerSys stockholders                 $ 965 $ 1,560 $ 747