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

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