EnerSys (ENS) 10-Q 6 Aug 14 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Jun. 29, 2014	Aug. 01, 2014
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	29-Jun-14	'
Document Fiscal Year Focus	'2015	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'ENS	'
Entity Registrant Name	'ENERSYS	'
Entity Central Index Key	'0001289308	'
Current Fiscal Year End Date	'--03-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	46,529,587

Consolidated_Condensed_Balance

Consolidated Condensed Balance Sheets (USD $)	Jun. 29, 2014	Mar. 31, 2014
Current assets:	'	'
Cash and cash equivalents	$234,898,000	$240,103,000
Accounts receivable, net of allowance for doubtful accounts: June 29, 2014 - $9,474; March 31, 2014 - $9,446	560,313,000	564,584,000
Total	384,194,000	361,846,000
Deferred taxes	64,009,000	64,765,000
Prepaid and other current assets	70,868,000	69,402,000
Total current assets	1,314,282,000	1,300,700,000
Property, plant, and equipment, net	371,712,000	370,166,000
Goodwill	422,937,000	426,056,000
Other intangible assets, net	170,687,000	172,472,000
Other assets	49,947,000	52,464,000
Total assets	2,329,565,000	2,321,858,000
Current liabilities:	'	'
Short-term debt	30,109,000	33,814,000
Current portion of long-term debt and capital lease obligations	327,000	354,000
Accounts payable	261,478,000	259,484,000
Accrued expenses	272,033,000	287,751,000
Total current liabilities	563,947,000	581,403,000
Long-term debt and capital lease obligations	328,490,000	288,132,000
Deferred taxes	97,638,000	101,149,000
Other liabilities	81,055,000	81,225,000
Total liabilities	1,071,130,000	1,051,909,000
Commitments and contingencies	'	'
Redeemable noncontrolling interests	7,880,000	8,047,000
Redeemable equity component of Convertible Notes	7,607,000	9,613,000
Equity:	'	'
Preferred Stock, $0.01 par value, 1,000,000 shares authorized, no shares issued or outstanding at June 29, 2014 and at March 31, 2014	0	0
Common Stock, $0.01 par value per share, 135,000,000 shares authorized; 53,619,794 shares issued and 46,635,974 shares outstanding at June 29, 2014; 53,263,348 shares issued and 46,942,126 shares outstanding at March 31, 2014	532,000	532,000
Additional paid-in capital	495,490,000	500,254,000
Treasury stock, at cost, 6,983,820 shares held as of June 29, 2014; 6,321,222 shares held as of March 31, 2014	-216,230,000	-170,643,000
Retained earnings	889,192,000	848,414,000
Accumulated other comprehensive income	68,131,000	67,845,000
Total EnerSys stockholders' equity	1,237,115,000	1,246,402,000
Noncontrolling interests	5,833,000	5,887,000
Total equity	1,242,948,000	1,252,289,000
Total liabilities and equity	$2,329,565,000	$2,321,858,000

Consolidated_Condensed_Balance1

Consolidated Condensed Balance Sheets (Parenthetical) (USD $)	Jun. 29, 2014	Mar. 31, 2014
In Thousands, except Share data, unless otherwise specified
Accounts receivable, allowance for doubtful accounts	$9,474	$9,446
Common Stock, par value	$0.01	$0.01
Common Stock, shares authorized	135,000,000	135,000,000
Common Stock, shares issued	53,619,794	53,263,348
Shares outstanding, beginning balance	46,635,974	46,942,126
Treasury stock, shares	6,983,820	6,321,222

Consolidated_Condensed_Stateme

Consolidated Condensed Statements of Income (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 29, 2014		Jun. 30, 2013
Net sales	$634,110		$597,297
Cost of goods sold	471,533		457,158
Gross profit	162,577		140,139
Operating expenses	89,059		77,110
Restructuring charges	1,829		421
Operating earnings	71,689	[1]	62,608	[1]
Interest expense	4,884		4,271
Other (income) expense, net	1,028		2,358
Earnings before income taxes	65,777		55,979
Income tax expense	16,662		15,562
Net earnings	49,115		40,417
Net losses attributable to noncontrolling interests	-54		-430
Net earnings attributable to EnerSys stockholders	$49,169		$40,847
Net earnings per common share attributable to EnerSys stockholders:	'		'
Basic earnings per common share attributable to EnerSys stockholders	$1.05		$0.85
Diluted earnings per common share attributable to EnerSys stockholders	$0.99		$0.83
Common Stock, Dividends, Per Share, Cash Paid	$0.18		$0.13
Weighted average shares of common stock outstanding:	'		'
Basic	46,899,303		47,868,982
Diluted	49,726,238		49,304,944
[1]	The Company does not allocate interest expense or other (income) expense to the reportable segments.

Consolidated_Condensed_Stateme1

Consolidated Condensed Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Net earnings	$49,115	$40,417
Other comprehensive income (loss):	'	'
Net unrealized gain (loss) on derivative instruments, net of tax	2,491	-1,488
Pension funded status adjustment, net of tax	185	201
Foreign currency translation adjustments	-2,557	-1,934
Total other comprehensive income (loss), net of tax	119	-3,221
Total comprehensive income	49,234	37,196
Comprehensive loss attributable to noncontrolling interests	-221	-1,231
Comprehensive income attributable to EnerSys stockholders	$49,455	$38,427

Consolidated_Condensed_Stateme2

Consolidated Condensed Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Cash flows from operating activities	'	'
Net earnings	$49,115	$40,417
Adjustments to reconcile net earnings to net cash provided by operating activities:	'	'
Depreciation and amortization	14,291	12,607
Restructuring Costs	365	0
Derivatives not designated in hedging relationships:	'	'
Net (gains) losses	10	226
Cash settlements	33	-208
Provision for doubtful accounts	250	-217
Deferred income taxes	58	153
Non-cash interest expense	2,262	2,235
Stock-based compensation	5,096	3,023
Loss (gain) on disposal of property, plant, and equipment	-17	-328
Changes in assets and liabilities, net of effects of acquisitions:	'	'
Accounts receivable	3,256	-21,395
Inventory	-24,423	13,080
Prepaid expenses and other current assets	1,469	-1,247
Other assets	1,626	156
Accounts payable	1,760	-6,020
Accrued expenses	-19,474	-7,896
Other liabilities	6,144	-194
Net cash provided by operating activities	41,821	34,392
Cash flows from investing activities	'	'
Capital expenditures	-14,761	-12,828
Proceeds from disposal of property, plant, and equipment	34	1,128
Net cash used in investing activities	-14,727	-11,700
Cash flows from financing activities	'	'
Net increase in short-term debt	-3,858	-478
Proceeds from revolving credit borrowings	81,600	0
Repayments of revolving credit borrowings	-43,000	0
Repayments of Convertible Debt	194	0
Capital lease obligations	-47	-83
Option proceeds (taxes paid related to net share settlement of equity awards), net	-12,664	-7,952
Excess tax benefits from exercise of stock options and vesting of equity awards	600	4,614
Purchase of treasury stock	-45,587	-21,993
Payments of Dividends	-8,196	-5,965
Net cash used in financing activities	-31,346	-31,857
Effect of exchange rate changes on cash and cash equivalents	-953	-125
Net increase in cash and cash equivalents	-5,205	-9,290
Cash and cash equivalents at beginning of period	240,103	249,348
Cash and cash equivalents at end of period	$234,898	$240,058

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	The accompanying interim unaudited consolidated condensed financial statements of EnerSys (the “Company”) have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and notes required for complete financial statements. In the opinion of management, the unaudited consolidated condensed financial statements include all normal recurring adjustments considered necessary for the fair presentation of the financial position, results of operations, and cash flows for the interim periods presented. The financial statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company’s 2014 Annual Report on Form 10-K (SEC File No. 001-32253), which was filed on May 28, 2014 (the "2014 Annual Report").
	The Company reports interim financial information for 13-week periods, except for the first quarter, which always begins on April 1, and the fourth quarter, which always ends on March 31. The four quarters in fiscal 2015 end on June 29, 2014, September 28, 2014, December 28, 2014, and March 31, 2015, respectively. The four quarters in fiscal 2014 ended on June 30, 2013, September 29, 2013, December 29, 2013, and March 31, 2014, respectively.
	The consolidated condensed financial statements include the accounts of the Company and its wholly-owned subsidiaries and any partially owned subsidiaries that the Company has the ability to control. All intercompany transactions and balances have been eliminated in consolidation.
	The Company also consolidates certain subsidiaries in which the noncontrolling interest party has within its control the right to require the Company to redeem all or a portion of its interest in the subsidiary. The redeemable noncontrolling interests are reported at their estimated redemption value, and the amount presented in temporary equity is not less than the initial amount reported in temporary equity. Any adjustment to the redemption value impacts retained earnings but does not impact net income or comprehensive income. Noncontrolling interests which are redeemable only upon future events, the occurrence of which is not currently probable, are recorded at carrying value.
	Recently Issued Accounting Pronouncements
	In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) providing guidance on revenue from contracts with customers that will supersede most current revenue recognition guidance, including industry-specific guidance. The underlying principle is that an entity will recognize revenue to depict the transfer of goods or services to customers at an amount that the entity expects to be entitled to in exchange for those goods or services. The guidance is effective for the interim and annual periods beginning on or after December 15, 2016 (early adoption is not permitted). The guidance permits the use of either a full retrospective or modified retrospective transition method. The Company has not yet selected a transition method and is currently evaluating the impact of the amended guidance on the consolidated financial position, results of operations and related disclosures.

Acquisitions_Notes

Acquisitions (Notes)	3 Months Ended
	Jun. 29, 2014
Acquisitions [Abstract]	'
Business Combination Disclosure [Text Block]	'
	Acquisitions
	In fiscal 2014, the Company completed the acquisition of Purcell Systems, Inc., ("Purcell") Quallion, LLC., ("Quallion"), and UTS Holdings Sdn. Bhd. and its subsidiaries ("UTS") and assigned values and useful lives to assets acquired based on preliminary valuations. During the first quarter of fiscal 2015, the Company completed purchase accounting for Purcell and based on final valuations performed, trademarks were valued at $16,800, technology at $7,900, customer relationships at $35,700, and goodwill was recorded at $50,889. The useful lives of technology and customer relationships were estimated at 10 and 9 years, respectively. Trademarks were considered to be indefinite-lived assets.
	During the first quarter of fiscal 2015, the Company also completed purchase accounting for Quallion and based on final valuations performed, trademarks were valued at $500, technology at $4,400, customer relationships at $3,400, and goodwill was recorded at $13,502. The useful lives of technology and customer relationships were estimated at 20 and 14 years, respectively. Trademarks were considered to be indefinite-lived assets.
	The Company expects to complete purchase accounting for UTS during fiscal 2015.

Inventories

Inventories	3 Months Ended
	Jun. 29, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	Inventories
	Inventories, net consist of:
		June 29, 2014		March 31, 2014
	Raw materials	$	94,149	$	87,469
	Work-in-process	120,609		116,124
	Finished goods	169,436		158,253
	Total	$	384,194	$	361,846

Goodwill_Changes_Notes

Goodwill Changes (Notes)	3 Months Ended
	Jun. 29, 2014
Goodwill Changes [Abstract]	'
Goodwill and Intangible Assets Disclosure [Text Block]	'
	Goodwill
	The changes in the carrying amount of goodwill during the current quarter of fiscal 2015 by reportable segment are as follows:
		Quarter ended June 29, 2014
		Americas			EMEA			Asia		Total
	Balance at beginning of year	$	215,630		$	177,586		$	32,840	$	426,056
	Adjustments related to the finalization of purchase accounting for Purcell	(3,256		)	—			—		(3,256		)
	Foreign currency translation adjustment	321			(325		)	141		137
	Balance at end of year	$	212,695		$	177,261		$	32,981	$	422,937

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The following tables represent the financial assets and (liabilities) measured at fair value on a recurring basis as of June 29, 2014 and March 31, 2014:
			Total Fair Value			Quoted Price in				Significant			Significant
			Measurement			Active  Markets				Other			Unobservable
			June 29,			for Identical				Observable			Inputs
			2014			Assets				Inputs			(Level 3)
						(Level 1)				(Level 2)
	Lead forward contracts		$	1,316		$	—			$	1,316		$	—
	Foreign currency forward contracts		468			—				468			—
	Total derivatives		$	1,784		$	—			$	1,784		$	—
			Total Fair Value			Quoted Price in				Significant			Significant
			Measurement			Active Markets				Other			Unobservable
			March 31,			for Identical				Observable			Inputs
			2014			Assets				Inputs			(Level 3)
						(Level 1)				(Level 2)
	Lead forward contracts		$	(2,371	)	$	—			$	(2,371	)	$	—
	Foreign currency forward contracts		113			—				113			—
	Total derivatives		$	(2,258	)	$	—			$	(2,258	)	$	—
	The fair values of lead forward contracts are calculated using observable prices for lead as quoted on the London Metal Exchange (“LME”) and, therefore, were classified as Level 2 within the fair value hierarchy, as described in the Company's consolidated financial statements included in its 2014 Annual Report in Note 1, Summary of Significant Accounting Policies.
	The fair values for foreign currency forward contracts are based upon current quoted market prices and are classified as Level 2 based on the nature of the underlying market in which these derivatives are traded.
	Financial Instruments
	The fair values of the Company’s cash and cash equivalents, accounts receivable and accounts payable approximate carrying value due to their short maturities.
	The fair value of the Company’s short-term debt approximates its carrying value, as it is variable rate debt and the terms are comparable to market terms as of the balance sheet dates and is classified as Level 2.
	The Company’s senior 3.375% convertible notes (“Convertible Notes”), with an original face value of $172,500, were issued when the Company’s stock price was trading at $30.19 per share. On June 29, 2014, the Company’s stock price closed at $68.91 per share. The conversion rate of the Convertible Notes as of July 1, 2014, the date when the the holders were notified that they can submit the Convertible Notes for conversion was 24.9008 shares of the Company's common stock per one thousand dollars in principal amount of the Convertible Notes, which equated to $40.16 per share. The conversion rate may be adjusted in accordance with the terms of the Convertible Notes and the indenture under which the Convertible Notes were issued. The fair value of these notes represent the trading values based upon quoted market prices and are classified as Level 2. The Convertible Notes were trading at 173% of face value on June 29, 2014 and at 175% of face value on March 31, 2014. See Note 11 for further details.
	The carrying amounts and estimated fair values of the Company’s derivatives and Convertible Notes at June 29, 2014 and March 31, 2014 were as follows:
			29-Jun-14										31-Mar-14
			Carrying					Fair Value					Carrying			Fair Value
			Amount										Amount
	Financial assets:
	Derivatives (1)		$	1,784				$	1,784				$	113		$	113
	Financial liabilities:
	Convertible Notes		$	164,699		(2)		$	298,089			(3)	$	162,887	(2)	$	301,875	(3)
	Derivatives (1)		—					—					2,371			2,371
	-1	Represents lead and foreign currency hedges.
	-2	The carrying amounts of the Convertible Notes at June 29, 2014 and March 31, 2014 represent the $172,306 and $172,500 principal value, less the unamortized debt discount (see Note 11 for further details).
	-3	The fair value amounts of the Convertible Notes at June 29, 2014 and March 31, 2014 represent the trading values of the Convertible Notes with a principal value of $172,306 and $172,500, respectively.

Derivative_Financial_Instrumen

Derivative Financial Instruments	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Derivative Financial Instruments	'
	Derivative Financial Instruments
	The Company utilizes derivative instruments to reduce its exposure to fluctuations in commodity prices and foreign exchange rates under established procedures and controls. The Company does not enter into derivative contracts for speculative purposes. The Company’s agreements are with creditworthy financial institutions and the Company anticipates performance by counterparties to these contracts and therefore no material loss is expected.
	Derivatives in Cash Flow Hedging Relationships
	Lead Hedge Forward Contracts
	The Company enters into lead hedge forward contracts to fix the price for a portion of its lead purchases. Management considers the lead hedge forward contracts to be effective against changes in the cash flows of the underlying lead purchases. The vast majority of such contracts are for a period not extending beyond one year and the notional amounts at June 29, 2014 and March 31, 2014 were 103.2 million pounds and 89.9 million pounds, respectively.
	Foreign Currency Forward Contracts
	The Company uses foreign currency forward contracts and purchased options to hedge a portion of the Company’s foreign currency exposures for lead as well as other foreign currency exposures so that gains and losses on these contracts offset changes in the underlying foreign currency denominated exposures. The vast majority of such contracts are for a period not extending beyond one year. As of June 29, 2014 and March 31, 2014, the Company had entered into a total of $72,730 and $70,332, respectively, of such contracts.
	In the coming twelve months, the Company anticipates that $339 of pretax gain relating to lead and foreign currency forward contracts will be reclassified from accumulated other comprehensive income (“AOCI”) as part of cost of goods sold. This amount represents the current unrealized impact of hedging lead and foreign exchange rates, which will change as market rates change in the future, and will ultimately be realized in the income statement as an offset to the corresponding actual changes in lead costs to be realized in connection with the variable lead cost and foreign exchange rates being hedged.
	Derivatives not Designated in Hedging Relationships
	Foreign Currency Forward Contracts
	The Company also enters into foreign currency forward contracts to economically hedge foreign currency fluctuations on intercompany loans and foreign currency denominated receivables and payables. These are not designated as hedging instruments and changes in fair value of these instruments are recorded directly in the Consolidated Condensed Statements of Income. As of June 29, 2014 and March 31, 2014, the notional amount of these contracts was $19,188 and $22,461, respectively.
	Presented below in tabular form is information on the location and amounts of derivative fair values in the Consolidated Condensed Balance Sheets and derivative gains and losses in the Consolidated Condensed Statements of Income:
	Fair Value of Derivative Instruments
	June 29, 2014 and March 31, 2014
			Derivatives and Hedging Activities Designated as Cash Flow Hedges								Derivatives and Hedging Activities Not Designated as Hedging Instruments
			29-Jun-14				31-Mar-14				29-Jun-14		31-Mar-14
	Prepaid and other current assets
	Foreign currency forward contracts		$	410			$	12			$	58	$	101
	Lead hedge forward contracts		1,291				—				—		—
	Other assets
	Lead hedge forward contracts		25				—				—		—
	Total assets		$	1,726			$	12			$	58	$	101
	Accrued expenses
	Lead hedge forward contracts		$	—			$	2,371			$	—	$	—
	Total liabilities		$	—			$	2,371			$	—	$	—
	The Effect of Derivative Instruments on the Consolidated Condensed Statements of Income
	For the quarter ended June 29, 2014
	Derivatives Designated as Cash Flow Hedges		Pretax Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)				Location of Gain (Loss)  Reclassified from AOCI into Income (Effective Portion)		Pretax Gain (Loss) Reclassified from AOCI into Income (Effective Portion)
	Lead hedge contracts		$	3,036			Cost of goods sold		$	(528	)
	Foreign currency forward contracts		502				Cost of goods sold		120
	Total		$	3,538					$	(408	)
	Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative		Pretax Gain (Loss)
	Foreign currency forward contracts	Other (income) expense, net		$	(10	)
	Total			$	(10	)
	The Effect of Derivative Instruments on the Consolidated Condensed Statements of Income
	For the quarter ended June 30, 2013
	Derivatives Designated as Cash Flow Hedges		Pretax Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)				Location of Gain (Loss)  Reclassified from AOCI into Income (Effective Portion)		Pretax Gain (Loss) Reclassified from AOCI into Income (Effective Portion)
	Lead hedge contracts		$	(303	)		Cost of goods sold		$	2,046
	Foreign currency forward contracts		(606		)		Cost of goods sold		(591		)
	Total		$	(909	)				$	1,455
	Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative		Pretax Gain (Loss)
	Foreign currency forward contracts	Other (income) expense, net		$	(226	)
	Total			$	(226	)

Income_Taxes

Income Taxes	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Income Taxes	'
	Income Taxes
	The Company’s income tax provision consists of federal, state and foreign income taxes. The tax provision for the first quarters of fiscal 2015 and 2014 were based on the estimated effective tax rates applicable for the full years ending March 31, 2015 and March 31, 2014, respectively, after giving effect to items specifically related to the interim periods.
	The effective income tax rates for the first quarters of fiscal 2015 and 2014 were 25.3% and 27.8%, respectively. The rate decrease in the first quarter of fiscal 2015 compared to the prior year quarter is primarily due to a reduction in income taxes from the release of a previously recognized valuation allowance related to one of our domestic subsidiaries and changes in the mix of earnings among tax jurisdictions.

Warranties

Warranties	3 Months Ended
	Jun. 29, 2014
Disclosure Analysis Of Changes In Liability For Product Warranties [Abstract]	'
Warranties	'
	Warranties
	The Company provides for estimated product warranty expenses when the related products are sold, with related liabilities included within accrued expenses and other liabilities. Because warranty estimates are forecasts that are based on the best available information, primarily historical claims experience, claims costs may differ from amounts provided. An analysis of changes in the liability for product warranties is as follows:
		Quarter ended
		29-Jun-14			30-Jun-13
	Balance at beginning of period	$	40,426		$	42,591
	Current period provisions	4,515			5,343
	Costs incurred	(3,564		)	(5,753		)
	Foreign currency translation adjustment	(61		)	21
	Balance at end of period	$	41,316		$	42,202

Commitments_Contingencies_and_

Commitments, Contingencies and Litigation	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Commitments, Contingencies and Litigation	'
	Commitments, Contingencies and Litigation
	Litigation and Other Legal Matters
	The Company is involved in litigation incidental to the conduct of its business, the results of which, in the opinion of management, are not likely to be material to the Company’s financial position, results of operations, or cash flows.
	Altergy
	In the fourth quarter of fiscal 2014, the Company recorded a $58,184 legal proceedings charge in connection with an adverse arbitration result involving disputes between the Company's wholly-owned subsidiary, EnerSys Delaware Inc. (“EDI”), and Altergy Systems (“Altergy”). EDI and Altergy were parties to a Supply and Distribution Agreement (the “SDA”) pursuant to which EDI was, among other things, granted the exclusive right to distribute and sell certain fuel cell products manufactured by Altergy for various applications throughout the United States. Commencing in 2011, various disputes arose and, because of the mandatory arbitration provision in the SDA, an arbitration action was filed by EDI in November 2012 seeking arbitration of claims relating to the SDA. In February 2013, EDI terminated the SDA. Following unsuccessful attempts to resolve their disputes by mediation in July 2013, the parties moved forward with arbitration in August 2013, where each party asserted various claims against the other.
	After discovery, a hearing and post-hearing submissions by each party, on May 13, 2014, the arbitration panel issued an award in favor of Altergy. As a result, the arbitration panel concluded that Altergy should recover $58,184 in net money damages from EDI. On May 13, 2014, Altergy filed a petition with the U.S. District Court for the Northern District of California (the “District Court”) seeking to confirm the arbitration panel award as well as post-award, prejudgment interest at the rate of 5.75% and post-judgment interest at the applicable federal statutory rate.
	On July 11, 2014, EDI filed a motion to vacate this award with the District Court. A hearing is scheduled before the District Court in late September 2014. While we are currently pursuing legal challenges of this award, there can be no assurances that this challenge will ultimately be successful. The full amount of the award was recorded in the fourth quarter of fiscal 2014 with an after tax expense of approximately $35,667. Adjustments to the accrual may be made in future periods depending on the outcome of this challenge.
	Environmental Issues
	As a result of its operations, the Company is subject to various federal, state, and local, as well as international environmental laws and regulations and is exposed to the costs and risks of handling, processing, storing, transporting, and disposing of hazardous substances, especially lead and acid. The Company’s operations are also subject to federal, state, local and international occupational safety and health regulations, including laws and regulations relating to exposure to lead in the workplace.
	The Company is responsible for certain cleanup obligations at the former Yuasa battery facility in Sumter, South Carolina that predates its ownership of this facility. This manufacturing facility was closed in 2001 and is separate from the Company’s current metal fabrication facility in Sumter. The Company has established a reserve for this facility. As of June 29, 2014 and March 31, 2014, the reserves related to this facility were $2,902 and $2,915, respectively. Based on current information, the Company’s management believes these reserves are adequate to satisfy the Company’s environmental liabilities at this facility.
	Lead Contracts
	To stabilize its costs, the Company has entered into contracts with financial institutions to fix the price of lead. The vast majority of such contracts are for a period not extending beyond one year. Under these contracts, at June 29, 2014 and March 31, 2014, the Company has hedged the price to purchase 103.2 million pounds and 89.9 million pounds of lead, respectively, for a total purchase price of $99,089 and $86,494, respectively.
	Foreign Currency Forward Contracts
	The Company quantifies and monitors its global foreign currency exposures. On a selective basis, the Company will enter into foreign currency forward and purchased option contracts to reduce the volatility from currency movements that affect the Company. The vast majority of such contracts are for a period not extending beyond one year. The Company’s largest exposure is from the purchase and conversion of U.S. dollar based lead costs into local currencies in EMEA. Additionally, the Company has currency exposures from intercompany and third party trade transactions. To hedge these exposures, the Company has entered into a total of $91,918 and $92,793, respectively, of foreign currency forward and purchased option contracts with financial institutions as of June 29, 2014 and March 31, 2014.

Restructuring_Plans

Restructuring Plans	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Restructuring Plans	'
	Restructuring Plans
	During fiscal 2013, the Company announced a restructuring related to improving the efficiency of its manufacturing operations in EMEA. The Company estimates that the total charges for these actions will amount to approximately $7,000, primarily from cash expenses for employee severance-related payments and non-cash expenses associated with the write-off of certain fixed assets and inventory. The Company estimates that these actions will result in the reduction of approximately 130 employees upon completion. The Company recorded restructuring charges of $6,463 through fiscal 2014, consisting of non-cash charges of $1,399 and cash charges of $5,064 and recorded an additional charge of $236 during the first quarter of fiscal 2015. The Company incurred $3,700 of costs against the accrual through fiscal 2014, and incurred $686 in costs against the accrual during the first quarter of fiscal 2015. As of June 29, 2014, the reserve balance associated with these actions is $948. The Company expects to be committed to an additional $301 of restructuring charges in fiscal 2015 related to these actions, and expects to complete the program during fiscal 2015.
	During fiscal 2014, the Company announced further restructuring programs to improve the efficiency of its manufacturing, sales and engineering operations in EMEA including the restructuring of its manufacturing operations in Bulgaria. The restructuring of the Bulgaria operations was announced during the third quarter of fiscal 2014 and consists of the transfer of motive power and a portion of reserve power battery manufacturing to the Company's facilities in Western Europe. The Company estimates that the total charges for all actions announced during fiscal 2014 will amount to approximately $23,700, primarily from non-cash charges related to the write-off of fixed assets and inventory of $11,000, along with cash charges for employee severance-related payments and other charges of $12,700. The Company estimates that these actions will result in the reduction of approximately 500 employees upon completion. During fiscal 2014, the Company recorded restructuring charges of $19,039 consisting of non-cash charges of $10,089 related to the write-off of fixed assets and inventory, and cash charges of $8,950 related to employee severance. During the first quarter of fiscal 2015 the Company recorded an additional charge of $1,593 consisting of non-cash charges of $365 related to the write-off of inventory, and $1,228 related to other cash charges. During fiscal 2014, the Company incurred $2,130 in costs against the accrual and incurred an additional $5,080 against the accrual during the first quarter of fiscal 2015. As of June 29, 2014, the reserve balance associated with these actions is $3,100. The Company expects to be committed to an additional $3,068 of restructuring charges in fiscal 2015 related to these actions, comprising of $2,522 in severance and other charges and $546 in non-cash charges and expects to complete the program during fiscal 2015.
	A roll-forward of the restructuring reserve is as follows:
		Employee			Other			Total
		Severance
	Balance as of March 31, 2014	$	7,312		$	1,102		$	8,414
	Accrued	875			589			1,464
	Costs incurred	(5,734		)	(32		)	(5,766		)
	Foreign currency impact and other	(48		)	(16		)	(64		)
	Balance as of June 29, 2014	$	2,405		$	1,643		$	4,048

Debt

Debt	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Debt	'
	Debt
	The following summarizes the Company’s long-term debt including capital lease obligations as of June 29, 2014 and March 31, 2014:
		29-Jun-14			31-Mar-14
	3.375% Convertible Notes, net of discount, due 2038	$	164,699		$	162,887
	2011 Credit Facility, due 2018	163,600			125,000
	Capital lease obligations and other	518			599
		328,817			288,486
	Less current portion	327			354
	Total long-term debt and capital lease obligations	$	328,490		$	288,132
	3.375% Convertible Notes
	The Convertible Notes will mature on June 1, 2038, unless earlier converted, redeemed or repurchased. Prior to maturity, the holders may convert their Convertible Notes into shares of the Company’s common stock at any time after March 1, 2015 or prior to that date under certain circumstances. When issued, the initial conversion rate was 24.6305 shares of the Company's common stock per one thousand dollars in principal amount of Convertible Notes, which was equivalent to an initial conversion price of $40.60 per share. The conversion rate as of July 1, 2014, the most recent date when the the holders were notified that they can submit the Convertible Notes for conversion, was 24.9008 shares of the Company's common stock per one thousand dollars in principal amount of the Convertible Notes due to the cumulative impact of cash dividends paid on the Company's common stock. The conversion price is subject to adjustment under certain circumstances. It is the Company’s current intent to settle the principal amount of any conversions in cash, and any additional conversion consideration in cash, shares of the Company's common stock or a combination of cash and shares.
	At any time after June 6, 2015, the Company may at its option redeem the Convertible Notes, in whole or in part, for cash, at a redemption price equal to 100% of the principal amount of Convertible Notes to be redeemed, plus any accrued and unpaid interest.
	Holders may convert their Convertible Notes prior to March 1, 2015, at the option of the holder, under the following circumstances: (i) during any calendar quarter (and only during such calendar quarter), if the last reported sale price (as defined in the indenture for the Convertible Notes) of a share of the Company's common stock for 20 or more trading days in a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter exceeds 130% of the applicable conversion price in effect for the Convertible Notes on the last trading day of the immediately preceding calendar quarter, (ii) upon the occurrence of specified corporate events, or (iii) during the five business-day period after any five consecutive trading day period (the “measurement period”) in which the “trading price” (as defined in the indenture for the Convertible Notes) of the Convertible Notes for each day of the measurement period was less than 98% of the product of the “last reported sale price” (as defined in the indenture for the Convertible Notes) of a share of the Company's common stock and the applicable conversion rate on such day.
	At June 30, 2014, the closing price of the Company's common stock exceeded 130% of the conversion price for more than 20 trading days during the period of 30 consecutive trading days ending June 30, 2014, thereby satisfying one of the early conversion events and as a result, the Convertible Notes became convertible on demand, and the holders were notified that they can elect to submit the Convertible Notes for conversion, between the notification date of July 1, 2014 and September 30, 2014. The carrying value of the Convertible Notes of $164,699 continues to be reported as long-term debt on the Consolidated Condensed Balance Sheet as of June 29, 2014 as the Company intends to draw on the 2011 Credit Facility to settle, at a minimum, the principal amount of any such conversions in cash. No gain or loss was recognized when the Convertible Notes became convertible.
	This optional conversion period is reset each quarter and the Company will reassess on the last day of each calendar quarter.
	In addition, upon becoming convertible, a portion of the equity component that was recorded upon the issuance of the Convertible Notes was considered redeemable and that portion of the equity was reclassified to temporary equity in the consolidated balance sheet. Such amount was determined based on the cash consideration to be paid upon conversion and the carrying amount of the debt. As the holders of the Convertible Notes will be paid in cash for the principal amount and issued shares or a combination of cash and shares for the remaining value of the Convertible Notes, the reclassification into temporary equity as of June 29, 2014 was $7,607 based on the Convertible Notes principal of $172,306 and the carrying value of $164,699. If a conversion event takes place in the following quarter, this temporary equity balance will be recalculated based on the difference between the Convertible Notes principal and the debt carrying value. If the Convertible Notes are settled during the second quarter of fiscal 2015, an amount equal to the fair value of the liability component immediately prior to the settlement will be deducted from the fair value of the total settlement consideration transferred and allocated to the liability component. Any difference between the amount allocated to the liability and the net carrying amount of the Convertible Notes (including any unamortized debt issue costs and discount) will be recognized in earnings as a gain or loss on debt extinguishment. Any remaining consideration is allocated to the reacquisition of the equity component and will be recognized as a reduction of EnerSys stockholders’ equity.
	The following represents the principal amount of the liability component, the unamortized discount, and the net carrying amount of the Convertible Notes as of June 29, 2014 and March 31, 2014:
		29-Jun-14			31-Mar-14
	Principal	$	172,306		$	172,500
	Unamortized discount	(7,607		)	(9,613		)
	Net carrying amount	$	164,699		$	162,887
	As of June 29, 2014, the remaining discount will be amortized over a period of 11 months. The conversion price of the $172,306 in aggregate principal amount of the Convertible Notes as of July 1, 2014, equated to $40.16 per share and the number of shares on which the aggregate consideration is to be delivered upon conversion is 4,290,557.
	The effective interest rate on the liability component of the Convertible Notes was 8.50%. The amount of interest cost recognized for the amortization of the discount on the liability component of the Convertible Notes was $2,006 and $1,844, respectively, during the quarters ended June 29, 2014 and June 30, 2013.
	2011 Credit Facility
	The Company is party to a $350,000 senior secured revolving credit facility (as amended, “2011 Credit Facility”) and, on July 8, 2014, amended the credit facility while also entering into an Incremental Commitment Agreement (“Incremental Commitment Agreement”) pursuant to which certain banks agreed to provide incremental term loan commitments of $150,000 and incremental revolving commitments of $150,000. Pursuant to these changes, the 2011 Credit Facility is now comprised of a $500,000 senior secured revolving credit facility and a $150,000 senior secured incremental term loan credit facility which matures on September 30, 2018. The 2011 Credit Facility may be increased by an aggregate amount of $300,000 in revolving commitments and/or one or more new tranches of term loans, under certain conditions. Both revolving loans and incremental term loans under the 2011 Credit Facility will bear interest, at the Company's option, at a rate per annum equal to either (i) the London Interbank Offered Rate (“LIBOR”) plus between 1.25% and 1.75% (based on the Company's consolidated net leverage ratio) or (ii) the Base Rate (which is the highest of (a) the Bank of America prime rate, and (b) the Federal Funds Effective Rate) plus between 0.25% and 0.75% (based on the Company’s consolidated net leverage ratio).
	As of June 29, 2014, the Company had $163,600 outstanding in revolver borrowings.
	Short-Term Debt
	As of June 29, 2014 and March 31, 2014, the Company had $30,109 and $33,814, respectively, of short-term borrowings. The weighted-average interest rates on these borrowings were approximately 9% and 7%, respectively.
	Available Lines of Credit
	As of June 29, 2014 and March 31, 2014, the Company had available and undrawn, under all its lines of credit, $317,560 and $360,275, respectively, including $132,960 and $136,525, of uncommitted lines of credit as of June 29, 2014 and March 31, 2014, respectively.
	As of June 29, 2014 and March 31, 2014, the Company had $4,035 and $1,653, respectively, of standby letters of credit.

Retirement_Plans

Retirement Plans	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Retirement Plans	'
	Retirement Plans
	The following tables present the components of the Company’s net periodic benefit cost related to its defined benefit pension plans:
		United States Plans						International Plans
		Quarter ended						Quarter ended
		29-Jun-14			30-Jun-13			29-Jun-14			30-Jun-13
	Service cost	$	102		$	91		$	211		$	200
	Interest cost	169			156			680			580
	Expected return on plan assets	(221		)	(199		)	(592		)	(511		)
	Amortization and deferral	87			133			178			104
	Net periodic benefit cost	$	137		$	181		$	477		$	373

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Stock-Based Compensation	'
	Stock-Based Compensation
	As of June 29, 2014, the Company maintains the EnerSys 2010 Equity Incentive Plan (“2010 EIP”). The 2010 EIP reserved 3,177,477 shares of common stock for the grant of various types of equity awards including nonqualified stock options, restricted stock, restricted stock units, market share units and other forms of stock-based compensation.
	The Company recognized stock-based compensation expense associated with its equity incentive plans of $5,096 for the first quarter of fiscal 2015 and $3,023 for the first quarter of fiscal 2014.
	During the quarter ended June 29, 2014, the Company granted to non-employee directors 1,064 restricted stock units, pursuant to the EnerSys Deferred Compensation Plan for Non-Employee Directors.
	During the quarter ended June 29, 2014, the Company granted to management and other key employees 76,512 non-qualified stock options that vest three years from the date of grant, 118,312 restricted stock units that vest 25% each year over four years from the date of grant, and 152,300 market share units that vest three years from the date of grant.
	Common stock activity during the quarter ended June 29, 2014 included the vesting of 175,587 restricted stock units and 384,448 market share units.
	As of June 29, 2014, there were 142,685 non-qualified stock options, 505,316 restricted stock units and 619,952 market share units outstanding.

Stockholders_Equity

Stockholders' Equity	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Stockholders' Equity	'
	Stockholders’ Equity and Noncontrolling Interests
	Common Stock
	The following demonstrates the change in the number of shares of common stock outstanding during the first quarter ended June 29, 2014:
	Shares outstanding as of March 31, 2014	46,942,126
	Purchase of treasury stock	(662,598	)
	Shares issued as part of equity-based compensation plans, net of equity awards surrendered for option price and taxes	356,446
	Shares outstanding as of June 29, 2014	46,635,974
	Treasury Stock
	During the first quarter ended June 29, 2014, the Company purchased 662,598 shares of its common stock for $45,587. At June 29, 2014 and March 31, 2014, the Company held 6,983,820 and 6,321,222 shares as treasury stock, respectively.
	Accumulated Other Comprehensive Income ("AOCI")
	The components of AOCI, net of tax, as of June 29, 2014 and June 30, 2013, are as follows:
		31-Mar-14			Before Reclassifications			Amounts Reclassified from AOCI			29-Jun-14
	Pension funded status adjustment	$	(15,207	)	$	—		$	185		$	(15,022	)
	Net unrealized (loss) gain on derivative instruments	(2,253		)	2,234			257			238
	Foreign currency translation adjustment	85,305			(2,390		)	—			82,915
	Accumulated other comprehensive income	$	67,845		$	(156	)	$	442		$	68,131
		31-Mar-13			Before Reclassifications			Amounts Reclassified from AOCI			30-Jun-13
	Pension funded status adjustment	$	(13,169	)	$	—		$	201		$	(12,968	)
	Net unrealized (loss) on derivative instruments	(832		)	(573		)	(915		)	(2,320		)
	Foreign currency translation adjustment	54,656			(1,133		)	—			53,523
	Accumulated other comprehensive income	$	40,655		$	(1,706	)	$	(714	)	$	38,235
	The following table presents reclassifications from AOCI during the first quarter ended June 29, 2014:
	Components of AOCI	Amounts Reclassified from AOCI			Location of Loss Recognized on Income Statement
	Derivatives in Cash Flow Hedging Relationships:
	Net unrealized loss on derivative instruments	$	408
	Tax benefit	(151		)
	Net unrealized loss on derivative instruments, net of tax	$	257		Cost of goods sold
	Defined benefit pension costs:
	Prior service costs and deferrals	$	265
	Tax benefit	(80		)
	Net periodic benefit cost, net of tax	$	185		Net periodic benefit cost, included in Cost of goods sold, Operating expenses - See Note 12
	The following table presents reclassifications from AOCI during the first quarter ended June 30, 2013:
	Components of AOCI	Amounts Reclassified from AOCI			Location of (Gain) Loss
					Recognized on Income Statement
	Derivatives in Cash Flow Hedging Relationships:
	Net unrealized (gain) on derivative instruments	$	(1,455	)
	Tax expense	540
	Net unrealized (gain) on derivative instruments, net of tax	$	(915	)	Cost of goods sold
	Defined benefit pension costs:
	Prior service costs and deferrals	$	237
	Tax benefit	(36		)
	Net periodic benefit cost, net of tax	$	201		Net periodic benefit cost, included in Cost of goods sold, Operating expenses - See Note 12
	The following demonstrates the change in equity attributable to EnerSys stockholders and nonredeemable noncontrolling interests during the quarter ended June 29, 2014:
		Equity Attributable to EnerSys Stockholders			Nonredeemable Noncontrolling Interests			Total Equity
	Balance as of March 31, 2014	$	1,246,402		$	5,887		$	1,252,289
	Total comprehensive income:
	Net earnings	49,169			59			49,228
	Net unrealized gain on derivative instruments, net of tax	2,491			—			2,491
	Pension funded status adjustment, net of tax	185			—			185
	Foreign currency translation adjustment	(2,390		)	(113		)	(2,503		)
	Total other comprehensive income (loss), net of tax	286			(113		)	173
	Total comprehensive income (loss)	49,455			(54		)	49,401
	Other changes in equity:
	Purchase of treasury stock	(45,587		)	—			(45,587		)
	Cash dividends - common stock ($0.175 per share)	(8,196		)	—			(8,196		)
	Reclassification of redeemable equity component of Convertible Notes	2,006			—			2,006
	Other, including activity related to equity awards	(6,965		)	—			(6,965		)
	Balance as of June 29, 2014	$	1,237,115		$	5,833		$	1,242,948
	The following demonstrates the change in redeemable noncontrolling interests during the quarter ended June 29, 2014:
		Redeemable Noncontrolling Interests
	Balance as of March 31, 2014	$	8,047
	Net losses	(113		)
	Foreign currency translation adjustment	(54		)
Balance as of June 29, 2014	$	7,880

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The following table sets forth the reconciliation from basic to diluted weighted-average number of common shares outstanding and the calculations of net earnings per common share attributable to EnerSys stockholders.
		Quarter ended
		29-Jun-14		30-Jun-13
	Net earnings attributable to EnerSys stockholders	$	49,169	$	40,847
	Weighted-average number of common shares outstanding:
	Basic	46,899,303		47,868,982
	Dilutive effect of:
	Common shares from exercise and lapse of equity awards, net of shares assumed reacquired	1,089,658		829,509
	Convertible Notes	1,737,277		606,453
	Diluted weighted-average number of common shares outstanding	49,726,238		49,304,944
	Basic earnings per common share attributable to EnerSys stockholders	$	1.05	$	0.85
	Diluted earnings per common share attributable to EnerSys stockholders	$	0.99	$	0.83
	Anti-dilutive equity awards not included in diluted weighted-average common shares	414		15,632
	The aggregate number of common shares that the Company could be obligated to issue upon conversion of its Convertible Notes, as of June 29, 2014, is 4,290,557. It is the Company’s current intent to settle the principal amount of any conversions in cash, and any additional conversion consideration ("conversion premium") in cash, shares of the Company’s common stock or a combination of cash and shares. During the first quarter of fiscal 2015, the average price of the Company's common stock of $67.94 per share exceeded the conversion price of $40.16 per share on the Convertible Notes. For the current quarter ended June 29, 2014, 1,737,277 shares relating to the conversion premium on the Convertible Notes were included in the diluted earnings per share using the "if converted" method.

Business_Segments

Business Segments	3 Months Ended
	Jun. 29, 2014
Disclosure Schedule Of Financial Data For Company Reportable Business Segments And Product Lines [Abstract]	'
Business Segments	'
	Business Segments
	The Company has three reportable business segments based on geographic regions, defined as follows:
	•	Americas, which includes North and South America, with segment headquarters in Reading, Pennsylvania, USA;
	•	EMEA, which includes Europe, the Middle East and Africa, with segment headquarters in Zurich, Switzerland; and
	•	Asia, which includes Asia, Australia and Oceania, with segment headquarters in Singapore.
	Summarized financial information related to the Company's reportable segments for the first quarters ended June 29, 2014 and June 30, 2013, is shown below:
			Quarter ended
			June 29, 2014			June 30, 2013
	Net sales by segment to unaffiliated customers
	Americas		$	330,928		$	315,623
	EMEA		241,935			230,967
	Asia		61,247			50,707
	Total net sales		$	634,110		$	597,297
	Net sales by product line
	Reserve power		$	311,374		$	292,819
	Motive power		322,736			304,478
	Total net sales		$	634,110		$	597,297
	Intersegment sales
	Americas		$	8,918		$	10,093
	EMEA		17,699			18,297
	Asia		11,459			7,711
	Total intersegment sales (1)		$	38,076		$	36,101
	Operating earnings by segment
	Americas		$	41,489		$	41,725
	EMEA		28,601			16,083
	Asia		3,428			5,221
	Restructuring charges - EMEA		(1,829		)	(421		)
	Total operating earnings (2)		$	71,689		$	62,608
	(1)	Intersegment sales are presented on a cost-plus basis, which takes into consideration the effect of transfer prices between legal entities.
	(2)	The Company does not allocate interest expense or other (income) expense to the reportable segments.

Subsequent_Events

Subsequent Events	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Subsequent Events	'
	Subsequent Events
	On August 5, 2014, the Company announced the declaration of a quarterly cash dividend of $0.175 per share of common stock to be paid on September 26, 2014, to stockholders of record as of September 12, 2014.
	On August 5, 2014, the Company also announced the establishment of an additional $60,000 stock repurchase authorization, which is in addition to the existing $70,000 stock repurchase authorization announced in May 2014 and the stock repurchase authorization in connection with the dilutive effects of previously granted equity-based awards.

Inventories_Tables

Inventories (Tables)	3 Months Ended
	Jun. 29, 2014
Inventory Disclosure [Abstract]	'
Summary Of Inventories	'
	Inventories, net consist of:
		June 29, 2014		March 31, 2014
	Raw materials	$	94,149	$	87,469
	Work-in-process	120,609		116,124
	Finished goods	169,436		158,253
	Total	$	384,194	$	361,846

Goodwill_Changes_Tables

Goodwill Changes (Tables)	3 Months Ended
	Jun. 29, 2014
Goodwill Changes [Abstract]	'
Schedule of Goodwill [Table Text Block]	'
	The changes in the carrying amount of goodwill during the current quarter of fiscal 2015 by reportable segment are as follows:
		Quarter ended June 29, 2014
		Americas			EMEA			Asia		Total
	Balance at beginning of year	$	215,630		$	177,586		$	32,840	$	426,056
	Adjustments related to the finalization of purchase accounting for Purcell	(3,256		)	—			—		(3,256		)
	Foreign currency translation adjustment	321			(325		)	141		137
	Balance at end of year	$	212,695		$	177,261		$	32,981	$	422,937

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Financial Assets And (Liabilities), Measured At Fair Value On A Recurring Basis	'
	The following tables represent the financial assets and (liabilities) measured at fair value on a recurring basis as of June 29, 2014 and March 31, 2014:
		Total Fair Value			Quoted Price in				Significant			Significant
		Measurement			Active  Markets				Other			Unobservable
		June 29,			for Identical				Observable			Inputs
		2014			Assets				Inputs			(Level 3)
					(Level 1)				(Level 2)
	Lead forward contracts	$	1,316		$	—			$	1,316		$	—
	Foreign currency forward contracts	468			—				468			—
	Total derivatives	$	1,784		$	—			$	1,784		$	—
		Total Fair Value			Quoted Price in				Significant			Significant
		Measurement			Active Markets				Other			Unobservable
		March 31,			for Identical				Observable			Inputs
		2014			Assets				Inputs			(Level 3)
					(Level 1)				(Level 2)
	Lead forward contracts	$	(2,371	)	$	—			$	(2,371	)	$	—
	Foreign currency forward contracts	113			—				113			—
	Total derivatives	$	(2,258	)	$	—			$	(2,258	)	$	—
Carrying Amounts And Estimated Fair Values Of Company's Financial Instruments	'
	The carrying amounts and estimated fair values of the Company’s derivatives and Convertible Notes at June 29, 2014 and March 31, 2014 were as follows:
		29-Jun-14										31-Mar-14
		Carrying					Fair Value					Carrying			Fair Value
		Amount										Amount
	Financial assets:
	Derivatives (1)	$	1,784				$	1,784				$	113		$	113
	Financial liabilities:
	Convertible Notes	$	164,699		(2)		$	298,089			(3)	$	162,887	(2)	$	301,875	(3)
	Derivatives (1)	—					—					2,371			2,371

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Fair Value of Derivative Instruments	'
	Presented below in tabular form is information on the location and amounts of derivative fair values in the Consolidated Condensed Balance Sheets and derivative gains and losses in the Consolidated Condensed Statements of Income:
	Fair Value of Derivative Instruments
	June 29, 2014 and March 31, 2014
		Derivatives and Hedging Activities Designated as Cash Flow Hedges				Derivatives and Hedging Activities Not Designated as Hedging Instruments
		29-Jun-14		31-Mar-14		29-Jun-14		31-Mar-14
	Prepaid and other current assets
	Foreign currency forward contracts	$	410	$	12	$	58	$	101
	Lead hedge forward contracts	1,291		—		—		—
	Other assets
	Lead hedge forward contracts	25		—		—		—
	Total assets	$	1,726	$	12	$	58	$	101
	Accrued expenses
	Lead hedge forward contracts	$	—	$	2,371	$	—	$	—
	Total liabilities	$	—	$	2,371	$	—	$	—
The Effect Of Derivative Instruments On Consolidated Condensed Statements Of Income	'

Warranties_Tables

Warranties (Tables)	3 Months Ended
	Jun. 29, 2014
Disclosure Analysis Of Changes In Liability For Product Warranties [Abstract]	'
Analysis Of Changes In Liability For Product Warranties	'
	An analysis of changes in the liability for product warranties is as follows:
		Quarter ended
		29-Jun-14			30-Jun-13
	Balance at beginning of period	$	40,426		$	42,591
	Current period provisions	4,515			5,343
	Costs incurred	(3,564		)	(5,753		)
	Foreign currency translation adjustment	(61		)	21
	Balance at end of period	$	41,316		$	42,202

Restructuring_Plans_Tables

Restructuring Plans (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Reconciliation of Restructuring Reserve	'
	A roll-forward of the restructuring reserve is as follows:
		Employee			Other			Total
		Severance
	Balance as of March 31, 2014	$	7,312		$	1,102		$	8,414
	Accrued	875			589			1,464
	Costs incurred	(5,734		)	(32		)	(5,766		)
	Foreign currency impact and other	(48		)	(16		)	(64		)
	Balance as of June 29, 2014	$	2,405		$	1,643		$	4,048

Debt_Tables

Debt (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Long-Term Debt And Capital Lease Obligations	'
	The following summarizes the Company’s long-term debt including capital lease obligations as of June 29, 2014 and March 31, 2014:
		29-Jun-14			31-Mar-14
	3.375% Convertible Notes, net of discount, due 2038	$	164,699		$	162,887
	2011 Credit Facility, due 2018	163,600			125,000
	Capital lease obligations and other	518			599
		328,817			288,486
	Less current portion	327			354
	Total long-term debt and capital lease obligations	$	328,490		$	288,132
Components Of Net Carrying Amount Of Convertible Notes	'
	The following represents the principal amount of the liability component, the unamortized discount, and the net carrying amount of the Convertible Notes as of June 29, 2014 and March 31, 2014:
		29-Jun-14			31-Mar-14
	Principal	$	172,306		$	172,500
	Unamortized discount	(7,607		)	(9,613		)
	Net carrying amount	$	164,699		$	162,887

Retirement_Plans_Tables

Retirement Plans (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Net Periodic Benefit Cost Related To Defined Benefit Pension Plans	'
	The following tables present the components of the Company’s net periodic benefit cost related to its defined benefit pension plans:
		United States Plans						International Plans
		Quarter ended						Quarter ended
		29-Jun-14			30-Jun-13			29-Jun-14			30-Jun-13
	Service cost	$	102		$	91		$	211		$	200
	Interest cost	169			156			680			580
	Expected return on plan assets	(221		)	(199		)	(592		)	(511		)
	Amortization and deferral	87			133			178			104
	Net periodic benefit cost	$	137		$	181		$	477		$	373

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Change In Number Of Shares Of Common Stock Outstanding	'
	The following demonstrates the change in the number of shares of common stock outstanding during the first quarter ended June 29, 2014:
	Shares outstanding as of March 31, 2014	46,942,126
	Purchase of treasury stock	(662,598	)
	Shares issued as part of equity-based compensation plans, net of equity awards surrendered for option price and taxes	356,446
	Shares outstanding as of June 29, 2014	46,635,974
Components Of Accumulated Other Comprehensive Income	'
	The components of AOCI, net of tax, as of June 29, 2014 and June 30, 2013, are as follows:
		31-Mar-14			Before Reclassifications			Amounts Reclassified from AOCI			29-Jun-14
	Pension funded status adjustment	$	(15,207	)	$	—		$	185		$	(15,022	)
	Net unrealized (loss) gain on derivative instruments	(2,253		)	2,234			257			238
	Foreign currency translation adjustment	85,305			(2,390		)	—			82,915
	Accumulated other comprehensive income	$	67,845		$	(156	)	$	442		$	68,131
Noncontrolling Interest Disclosure [Text Block]	'
	The following demonstrates the change in equity attributable to EnerSys stockholders and nonredeemable noncontrolling interests during the quarter ended June 29, 2014:
		Equity Attributable to EnerSys Stockholders			Nonredeemable Noncontrolling Interests			Total Equity
	Balance as of March 31, 2014	$	1,246,402		$	5,887		$	1,252,289
	Total comprehensive income:
	Net earnings	49,169			59			49,228
	Net unrealized gain on derivative instruments, net of tax	2,491			—			2,491
	Pension funded status adjustment, net of tax	185			—			185
	Foreign currency translation adjustment	(2,390		)	(113		)	(2,503		)
	Total other comprehensive income (loss), net of tax	286			(113		)	173
	Total comprehensive income (loss)	49,455			(54		)	49,401
	Other changes in equity:
	Purchase of treasury stock	(45,587		)	—			(45,587		)
	Cash dividends - common stock ($0.175 per share)	(8,196		)	—			(8,196		)
	Reclassification of redeemable equity component of Convertible Notes	2,006			—			2,006
	Other, including activity related to equity awards	(6,965		)	—			(6,965		)
	Balance as of June 29, 2014	$	1,237,115		$	5,833		$	1,242,948

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Jun. 29, 2014
Text Block [Abstract]	'
Schedule of Weighted Average Number of Shares	'
	The following table sets forth the reconciliation from basic to diluted weighted-average number of common shares outstanding and the calculations of net earnings per common share attributable to EnerSys stockholders.
		Quarter ended
		29-Jun-14		30-Jun-13
	Net earnings attributable to EnerSys stockholders	$	49,169	$	40,847
	Weighted-average number of common shares outstanding:
	Basic	46,899,303		47,868,982
	Dilutive effect of:
	Common shares from exercise and lapse of equity awards, net of shares assumed reacquired	1,089,658		829,509
	Convertible Notes	1,737,277		606,453
	Diluted weighted-average number of common shares outstanding	49,726,238		49,304,944
	Basic earnings per common share attributable to EnerSys stockholders	$	1.05	$	0.85
	Diluted earnings per common share attributable to EnerSys stockholders	$	0.99	$	0.83
	Anti-dilutive equity awards not included in diluted weighted-average common shares	414		15,632

Business_Segments_Business_Seg

Business Segments Business Segments (Tables)	3 Months Ended
	Jun. 29, 2014
Segment Reporting [Abstract]	'
Selected Financial Data for Reportable Business Segments and Product Lines	'
	:
			Quarter ended
			June 29, 2014			June 30, 2013
	Net sales by segment to unaffiliated customers
	Americas		$	330,928		$	315,623
	EMEA		241,935			230,967
	Asia		61,247			50,707
	Total net sales		$	634,110		$	597,297
	Net sales by product line
	Reserve power		$	311,374		$	292,819
	Motive power		322,736			304,478
	Total net sales		$	634,110		$	597,297
	Intersegment sales
	Americas		$	8,918		$	10,093
	EMEA		17,699			18,297
	Asia		11,459			7,711
	Total intersegment sales (1)		$	38,076		$	36,101
	Operating earnings by segment
	Americas		$	41,489		$	41,725
	EMEA		28,601			16,083
	Asia		3,428			5,221
	Restructuring charges - EMEA		(1,829		)	(421		)
	Total operating earnings (2)		$	71,689		$	62,608
	(1)	Intersegment sales are presented on a cost-plus basis, which takes into consideration the effect of transfer prices between legal entities.
	(2)	The Company does not allocate interest expense or other (income) expense to the reportable segments.

Acquisitions_Details

Acquisitions (Details) (USD $)

0 Months Ended

In Thousands, unless otherwise specified

Oct. 08, 2013

Oct. 08, 2013

Oct. 08, 2013

Oct. 28, 2013

Oct. 28, 2013

Oct. 28, 2013

Oct. 08, 2013

Oct. 28, 2013

Oct. 08, 2013

Oct. 28, 2013

Oct. 08, 2013

Oct. 28, 2013

Purcell [Member]

Purcell [Member]

Purcell [Member]

Quallion [Member]

Quallion [Member]

Quallion [Member]

Trademarks [Member]

Trademarks [Member]

Minimum

Minimum

Maximum

Maximum

Technology Equipment [Member]

Customer Relationships [Member]

Goodwill [Member]

Technology Equipment [Member]

Customer Relationships [Member]

Goodwill [Member]

Purcell [Member]

Quallion [Member]

Purcell [Member]

Quallion [Member]

Purcell [Member]

Quallion [Member]

Technology and Customer Relationships [Member]

Technology and Customer Relationships [Member]

Technology and Customer Relationships [Member]

Technology and Customer Relationships [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Indefinite-lived Intangible Assets Acquired

'

'

'

'

'

'

$17

$1

'

'

'

'

Acquired Finite-lived Intangible Asset, Amount

8

36

'

4

3

'

'

'

'

'

'

'

Goodwill, Acquired During Period

'

'

$51

'

'

$14

'

'

'

'

'

'

Finite-Lived Intangible Asset, Useful Life

'

'

'

'

'

'

'

'

'10 years

'20 years

'9 years

'14 years

Inventories_Details

Inventories (Details) (USD $)	Jun. 29, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Raw materials	$94,149	$87,469
Work-in-process	120,609	116,124
Finished goods	169,436	158,253
Total	$384,194	$361,846

Goodwill_Changes_Schedule_of_C

Goodwill Changes Schedule of Changes in Carrying Amount of Goodwill by Business Segment (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014
Goodwill [Line Items]	'
Balance at beginning of year	$426,056
Adjustments related to the finalization of purchase accounting for Purcell	-3,256
Foreign currency translation adjustment	137
Balance at end of year	422,937
Americas	'
Goodwill [Line Items]	'
Balance at beginning of year	215,630
Adjustments related to the finalization of purchase accounting for Purcell	-3,256
Foreign currency translation adjustment	321
Balance at end of year	212,695
EMEA	'
Goodwill [Line Items]	'
Balance at beginning of year	177,586
Adjustments related to the finalization of purchase accounting for Purcell	0
Foreign currency translation adjustment	-325
Balance at end of year	177,261
Asia	'
Goodwill [Line Items]	'
Balance at beginning of year	32,840
Adjustments related to the finalization of purchase accounting for Purcell	0
Foreign currency translation adjustment	141
Balance at end of year	$32,981

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments (Financial Assets and (Liabilities)) (Details) (USD $)	Jun. 29, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	$1,784	($2,258)
Significant Other Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	'	-2,258
Lead hedge forward contracts	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	1,316	-2,371
Lead hedge forward contracts | Significant Other Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	'	-2,371
Foreign currency forward contracts	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	468	113
Foreign currency forward contracts | Significant Other Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative fair value	'	$113

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments (Carrying Amounts and Estimated Fair Values) (Details) (USD $)	Jun. 29, 2014		Mar. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Derivatives assets, Carrying Amount	$1,784	[1]	$113	[1]
Derivatives assets, Fair Value	'		113	[1]
Derivatives liabilities	0	[1]	2,371	[1]
Derivatives liabilities, Fair Value	'		2,371	[1]
Convertible Notes Payable	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Convertible Notes Payable	164,699	[2]	162,887	[2]
Convertible Notes, Fair Value	$298,089	[3]	$301,875	[3]
[1]	Represents lead and foreign currency hedges.
[2]	The carrying amounts of the Convertible Notes at JuneB 29, 2014 and MarchB 31, 2014 represent the $172,306 and $172,500 principal value, less the unamortized debt discount (see Note 11 for further details).
[3]	The fair value amounts of the Convertible Notes at JuneB 29, 2014 and MarchB 31, 2014 represent the trading values of the Convertible Notes with a principal value of $172,306 and $172,500, respectively.

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments (Additional Information) (Details) (USD $)	1 Months Ended	3 Months Ended		3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	31-May-08	Jun. 29, 2014	Mar. 31, 2014	Jun. 29, 2014	Mar. 31, 2014
				Convertible Notes Payable	Convertible Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Face value of debt instrument	'	$172,306	$172,500	$172,306	'
Debt Instrument Interest Rate	'	'	'	3.38%	'
Price of stock per share when convertible notes were issued	'	'	'	'	$30.19
Closing price of stock per share	'	'	'	$68.91	'
Conversion option price per share	$40.60	$40.16	'	$40.16	'
Debt Conversion, Converted Instrument, Shares Issued	24.6305	24.9008	'	'	'
Trading of convertible notes, face value, disclosed as a percentage	'	'	'	173.00%	175.00%

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Location and Amounts of Derivative Fair Values) (Details) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

In Thousands, unless otherwise specified

Jun. 29, 2014

Jul. 01, 2012

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Mar. 31, 2014

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 29, 2014

Mar. 31, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Other Income Expense

Other Income Expense

Cost of Sales

Cost of Sales

Cost of Sales

Cost of Sales

Accrued expenses

Accrued expenses

Accrued expenses

Accrued expenses

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Designated as Hedging Instrument

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Prepaid and other current assets

Prepaid and other current assets

Prepaid and other current assets

Prepaid and other current assets

Prepaid and other current assets

Other assets

Other assets

Accrued expenses

Not Designated as Hedging Instrument

Not Designated as Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Derivatives, Fair Value [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net

'

'

'

'

'

'

'

'

'

($10)

($226)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

($10)

($226)

'

'

'

'

Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net

'

'

'

3,538

-909

'

'

'

'

'

'

'

'

'

502

-606

'

'

'

'

3,036

-303

'

'

'

'

'

'

'

'

'

'

Pretax Gain (Loss) Reclassified from AOCI into Income (Effective Portion)

408

-1,455

'

-408

1,455

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

120

-591

-528

2,046

Derivatives assets, Fair Value

'

'

113

[1]

'

'

1,726

12

'

'

58

'

101

'

'

'

'

410

12

58

101

'

'

1,291

25

0

'

'

'

'

'

'

'

Derivatives liabilities, Fair Value

'

'

$2,371

[1]

'

'

'

'

$0

$2,371

'

'

'

$0

$0

'

'

'

'

'

'

'

'

'

'

'

$2,371

'

'

'

'

'

'

[1]

Represents lead and foreign currency hedges.

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Derivatives Designated as Cash Flow Hedges) (Details) (USD $)

3 Months Ended

In Thousands, unless otherwise specified

Jun. 29, 2014

Jul. 01, 2012

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Jun. 29, 2014

Jun. 30, 2013

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Dedesignated As Hedging Instrument

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Lead hedge forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Foreign currency forward contracts

Cost of Sales

Cost of Sales

Cost of Sales

Cost of Sales

Derivative Instruments, Gain (Loss) [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Pretax Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)

'

'

$3,538

($909)

$3,036

($303)

'

'

$502

($606)

'

'

Pretax Gain (Loss) Reclassified from AOCI into Income (Effective Portion)

$408

($1,455)

($408)

$1,455

'

'

($528)

$2,046

'

'

$120

($591)

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Derivatives Not Designated as Hedging Instruments) (Details) (Not Designated as Hedging Instrument, USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	($10)	($226)
Foreign currency forward contracts | Other Income Expense	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	($10)	($226)

Derivative_Financial_Instrumen5

Derivative Financial Instruments (Additional Information) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013	Mar. 31, 2014
Derivatives, Fair Value [Line Items]	'	'	'
Foreign currency contract, maturity	'1 year	'	'
Notional amount	$72,730	'	$70,332
Recorded expense in the consolidated condensed statements of income	-1,028	-2,358	'
Cost of Sales	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Derivative gain (loss) to be recorded in income within 12 months, before tax	339	'	'
Foreign currency forward contracts	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Notional amount	$19,188	'	$22,461
Lead hedge forward contracts	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Notional amount in pounds	103,200,000	'	89,900,000
Hedging Derivatives Maturity Upper Limit	'1 year	'	'

Income_Taxes_Additional_Inform

Income Taxes (Additional Information) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Disclosure Income Taxes Additional Information [Abstract]	'	'
Effective income tax rates	25.30%	27.80%
Deferred Income Tax Expense (Benefit)	$58	$153

Warranties_Analysis_of_Changes

Warranties (Analysis of Changes in the Liability) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Disclosure Analysis Of Changes In Liability For Product Warranties [Abstract]	'	'
Balance at beginning of period	$40,426	$42,591
Current period provisions	4,515	5,343
Costs incurred	-3,564	-5,753
Foreign exchange and other	-61	21
Balance at end of period	$41,316	$42,202

Commitments_Contingencies_and_1

Commitments Contingencies and Litigation (Additional Information) (Details) (USD $)	3 Months Ended	12 Months Ended				3 Months Ended	12 Months Ended	0 Months Ended	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Mar. 31, 2014	Mar. 31, 2014	Jun. 29, 2014	Mar. 31, 2014	Jun. 29, 2014	Mar. 31, 2014	13-May-14	Mar. 31, 2014	Jun. 29, 2014	Jun. 29, 2014
			Interest rate swap agreements	Foreign currency forward contracts	Foreign currency forward contracts	Lead hedge forward contracts	Lead hedge forward contracts	EnerSys Delaware Inc and Altergy Systems Litigation [Member]	EnerSys Delaware Inc and Altergy Systems Litigation [Member]	Maximum	Minimum
						lb	lb	EnerSys Delaware Inc. [Member]	EnerSys Delaware Inc. [Member]	Interest rate swap agreements	Interest rate swap agreements
Commitments, Contingencies And Litigation [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Derivative, Maturity Date	'	'	'	'	'	'	'	'	'	1-May-13	1-Feb-13
Derivative Type Of Convertible Interest Rate Swap	'	'	$85,000	'	'	'	'	'	'	'	'
Litigation Settlement, Amount	'	'	'	'	'	'	'	-58	-58	'	'
Litigation Settlement, Interest Rate	'	'	'	'	'	'	'	5.75%	'	'	'
Gain (Loss) Related to Litigation Settlement, Net of Tax	'	'	'	'	'	'	'	'	36	'	'
Provision For Environmental Liabilities	3	3	'	'	'	'	'	'	'	'	'
Purchase price of hedges, pounds of lead	'	'	'	'	'	103,200,000	89,900,000	'	'	'	'
Purchase price of hedges	'	'	'	$91,918	$92,793	$99,089	$86,494	'	'	'	'

Restructuring_Plans_Rollforwar

Restructuring Plans (Roll-forward of Restructuring Reserve) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Mar. 31, 2014
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve	$4,048	$8,414
Restructuring and Related Cost, Incurred Cost	1,464	'
Payments for Restructuring	-5,766	'
Restructuring Reserve, Translation Adjustment	-64	'
Employee Severance [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve	2,405	7,312
Restructuring and Related Cost, Incurred Cost	875	'
Payments for Restructuring	-5,734	'
Restructuring Reserve, Translation Adjustment	-48	'
Other Restructuring [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve	1,643	1,102
Restructuring and Related Cost, Incurred Cost	589	'
Payments for Restructuring	-32	'
Restructuring Reserve, Translation Adjustment	($16)	'

Restructuring_Plans_Additional

Restructuring Plans (Additional Information) (Details) (USD $)	3 Months Ended		6 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013	Sep. 30, 2012	Mar. 31, 2014
	Employee			Employee
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Charges related to restructuring plan	$1,464	'	'	'
Restructuring reserve	4,048	'	'	8,414
Restructuring charges	1,829	421	'	'
Restructuring charges, cash charges related to employee severance and other charges	5,766	'	'	'
Restructuring Costs	365	0	'	'
European Operations	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Expected reduction in number of employees	500	'	'	130
Charges related to restructuring plan	'	'	'	3,700
Restructuring charges	19,039	236	8,950	6,463
Restructuring charges, non-cash charges related to the write-off of fixed assets and inventory	11,000	'	'	1,399
Restructuring charges, cash charges related to employee severance and other charges	2,130	686	'	5,064
Restructuring Costs	23,700	'	'	7,000
Expected additional restructuring charges	301	'	'	'
European Operations | Restructuring Twenty Thirteen Actions	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring reserve	948	'	'	'
European Operations | Restructuring Twenty Fourteen Actions	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring reserve	3,100	'	'	'
European Operations | Restructuring Twenty Fifteen [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Expected additional restructuring charges	3,068	'	'	'
Non Cash Charges [Member] | European Operations	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges, cash charges related to employee severance and other charges	'	'	'	12,700
Restructuring Costs	10,089	'	'	'
Restructurings Related To Improving Efficiency Of Manufacturing Operations In Emea [Member] | European Operations | Restructuring Twenty Fourteen Actions	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges, cash charges related to employee severance and other charges	'	'	'	5
Restructurings Related To Improving Efficiency Of Manufacturing Operations In Emea [Member] | European Operations | Restructuring Twenty Fifteen [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges	2	'	'	'
Restructurings Related To Improving Efficiency Of Manufacturing Operations In Emea [Member] | Non Cash Charges [Member] | European Operations | Restructuring Twenty Fifteen [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges	1	'	'	'
Restructuring Costs	0	'	'	'
Restructurings Related To Improving Efficiency Of Manufacturing Operations In Emea [Member] | Cash Charges [Member] | European Operations | Restructuring Twenty Fourteen Actions	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges	1	'	'	'
Restructurings Related To Improving Efficiency Of Manufacturing Operations In Emea [Member] | Cash Charges [Member] | European Operations | Restructuring Twenty Fifteen [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Restructuring charges	$3	'	'	'

Debt_Longterm_Debt_Including_C

Debt (Long-term Debt Including Capital Lease Obligations) (Details) (USD $)	Jun. 29, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'	'
Capital lease obligations and other	$518	$599
Gross long-term debt and capital lease obligations	328,817	288,486
Less current portion	327	354
Long-term debt and capital lease obligations	328,490	288,132
Convertible Notes Payable	'	'
Debt Instrument [Line Items]	'	'
Long-term debt	164,699	162,887
2011 Credit Facility due 2018	'	'
Debt Instrument [Line Items]	'	'
Long-term debt	$163,600	$125,000

Debt_Convertible_Notes_Details

Debt (Convertible Notes) (Details) (Convertible Notes Payable, USD $)	Jun. 29, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Convertible Notes Payable	'	'
Principal	$172,306	$172,500
Unamortized discount	7,607	9,613
Long-term debt	$164,699	$162,887

Debt_Additional_Information_De

Debt (Additional Information) (Details) (USD $)

1 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

0 Months Ended

31-May-08

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 30, 2013

Mar. 31, 2014

Jun. 29, 2014

Mar. 31, 2014

Jun. 29, 2014

Jun. 29, 2014

Jun. 29, 2014

Jul. 08, 2014

Jul. 08, 2014

Jul. 08, 2014

Jul. 08, 2014

Jul. 08, 2014

Jul. 08, 2014

Jul. 08, 2014

Convertible Notes Payable

Convertible Notes Payable

Convertible Notes Payable

2011 Credit Facility due 2018

2011 Credit Facility due 2018

Minimum

Maximum

Senior Secured Revolving Credit Facility

Incremental Commitment Agreement

Incremental Commitment Agreement

Incremental Commitment Agreement

LIBOR

LIBOR

Base Rate

Base Rate

Line of Credit

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Incremental Commitment Agreement

Incremental Commitment Agreement

Incremental Commitment Agreement

Incremental Commitment Agreement

Revolving Credit Facility

Revolving Commitments and/or Term Loans

Line of Credit

Secured Debt

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Revolving Credit Facility

Revolving Commitments and/or Term Loans

Revolving Commitments and/or Term Loans

Revolving Commitments and/or Term Loans

Revolving Commitments and/or Term Loans

Minimum

Maximum

Minimum

Maximum

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Conversion, Converted Instrument, Shares Issued

24.6305

24.9008

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amortized remaining discount period

'

'11 months

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Face value of debt instrument

'

$172,306,000

$172,500,000

$172,306,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Conversion option price per share

$40.60

$40.16

'

$40.16

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Aggregate consideration on conversion shares

'

4,290,557

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest rate percentage

'

'

'

8.50%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount of interest cost recognized for the amortization of the discount

'

'

'

2,006,000

1,844,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Maximum Borrowing Capacity

'

'

'

'

'

'

'

'

'

'

350,000

'

500,000

150,000

'

'

'

'

Line of Credit Facility, Incremental Term Loan Commitment

'

'

'

'

'

'

'

'

'

'

'

'

'

150,000

'

'

'

'

Line of Credit Facility, Incremental Revolving Commitment

'

'

'

'

'

'

'

'

'

'

'

'

150,000

'

'

'

'

'

Short-term debt

'

30,109,000

33,814,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Short-term Debt, Weighted Average Interest Rate

'

9.00%

7.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Available lines of credit

'

'

'

317,560,000

'

360,275,000

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding amount

'

'

'

132,960,000

'

136,525,000

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Increase in Borrowing Capacity Limit

'

'

'

'

'

'

'

'

'

'

'

300,000

'

'

'

'

'

'

Debt Instrument, Basis Spread on Variable Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.25%

1.75%

0.25%

0.75%

Stand by letters of credit

'

'

'

4,035,000

'

1,653,000

'

'

'

'

'

'

'

'

'

'

'

'

Trading Days

'

'

'

'

'

'

'

'

'20 days

'30 days

'

'

'

'

'

'

'

'

Percentage of conversion price

'

'

'

'

'

'

'

'

98.00%

130.00%

'

'

'

'

'

'

'

'

Long-term debt

'

'

'

164,699,000

'

162,887,000

163,600,000

125,000,000

'

'

'

'

'

'

'

'

'

'

Convertible Notes, Fair Value

'

'

'

298,089,000

[1]

'

301,875,000

[1]

'

'

'

'

'

'

'

'

'

'

'

'

Temporary Equity, Carrying Amount, Attributable to Parent

'

$7,607,000

$9,613,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

The fair value amounts of the Convertible Notes at JuneB 29, 2014 and MarchB 31, 2014 represent the trading values of the Convertible Notes with a principal value of $172,306 and $172,500, respectively.

Retirement_Plans_Net_Periodic_

Retirement Plans (Net Periodic Benefit Cost) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
United States Pension Plans of US Entity, Defined Benefit	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Service cost	$102	$91
Interest cost	169	156
Expected return on plan assets	-221	-199
Amortization and deferral	-87	-133
Net periodic benefit cost	137	181
Foreign Pension Plans, Defined Benefit	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Service cost	211	200
Interest cost	680	580
Expected return on plan assets	-592	-511
Amortization and deferral	-178	-104
Net periodic benefit cost	$477	$373

StockBased_Compensation_Additi

Stock-Based Compensation (Additional Information) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Shares available for future grants	3,177,477	'
Equity-based compensation expense	$5,096	$3,023
Restricted Stock Units (RSUs)	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Vested restricted stock and restricted stock units	175,587	'
Stock option grants outstanding	505,316	'
Nonqualified Stock Options	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock option grants outstanding	142,685	'
Market Stock Units	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Vested restricted stock and restricted stock units	384,448	'
Stock option grants outstanding	619,952	'
Management | Restricted Stock Units (RSUs)	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock unit grants during period	1,064	'
Percentage of restricted stock units granted, vested per year	25.00%	'
Vesting period	'4 years	'
Management | Nonqualified Stock Options	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	76,512	'
Vesting period	'3 years	'
Management | Market Stock Units	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock unit grants during period	152,300	'
Vesting period	'3 years	'
Non-employee Directors [Member] | Restricted Stock Units (RSUs)	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock unit grants during period	118,312	'

Stockholders_Equity_Change_in_

Stockholders' Equity (Change in the Number of Shares of Common Stock Outstanding) (Details)	3 Months Ended
	Jun. 29, 2014	Mar. 31, 2014
Class of Stock [Line Items]	'	'
Shares outstanding, ending balance	46,635,974	46,942,126
Number of shares of common stock purchased	-662,598	'
Shares issued as part of equity-based compensation plans, net of equity awards surrendered for option price and taxes	356,446	'

Stockholders_Equity_Components

Stockholders' Equity (Components of Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013	Jul. 01, 2012	Mar. 31, 2014	Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'
Pension funded status adjustment	($15,207)	($13,169)	'	'	'
Unrealized gain on derivative instruments	-2,253	-832	'	'	'
Foreign currency translation adjustment	85,305	54,656	'	'	'
Accumulated other comprehensive income	68,131	'	38,235	67,845	40,655
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, [Abstract]	'	'	'	'	'
Amount recognized in AOCI, net of tax	0	'	0	'	'
Amount recognized in AOCI - Derivatives, net of tax	2,234	'	-573	'	'
Amount recognized in AOCI - CTA, net of tax	-2,390	'	-1,133	'	'
Accumulated other comprehensive income, Before-Tax Amount	-156	'	-1,706	'	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax [Abstract]	'	'	'	'	'
Amount reclassified out of AOCI, net of tax	185	201	201	'	'
Amount reclassified out of AOCI - Derivatives, net of tax	257	'	-915	'	'
Amount reclassified out of AOCI - CTA, net of tax	0	'	0	'	'
Accumulated other comprehensive income	442	'	-714	'	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract]	'	'	'	'	'
Pension funded status adjustment	-15,022	'	-12,968	'	'
Unrealized gain on derivative instruments	238	'	-2,320	'	'
Foreign currency translation adjustment	82,915	'	53,523	'	'
Accumulated other comprehensive income	$68,131	'	$38,235	$67,845	$40,655

Stockholders_Equity_Components1

Stockholders' Equity Components of AOCI (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013	Jul. 01, 2012
Equity [Abstract]	'	'	'
Net unrealized (gain) on derivative instruments	$408	'	($1,455)
Unrealized gain (loss) on derivative instruments, Tax Benefit (Expense)	-151	'	540
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount	257	'	-915
Pension funded status adjustment, Before-Tax Amount	265	'	237
Pension funded status adjustment, Tax Benefit (Expense)	80	'	36
Net periodic benefit cost, net of tax	$185	$201	$201

Stockholders_Equity_Noncontrol

Stockholders' Equity Noncontrolling Interests (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013	Jul. 01, 2012	Mar. 31, 2014
Noncontrolling Interest [Line Items]	'	'	'	'
Stockholders' Equity Attributable to Noncontrolling Interest	$5,833	'	'	$5,887
Net earnings attributable to noncontrolling interests	54	430	'	'
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount	257	'	-915	'
Amount reclassified out of AOCI, net of tax	185	201	201	'
Total other comprehensive income (loss), net of tax	119	-3,221	'	'
Total comprehensive income	49,234	37,196	'	'
Payments for Repurchase of Common Stock	45,587	21,993	'	'
Payments of Dividends	8,196	5,965	'	'
Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature	-2,006	'	'	'
Redeemable Noncontrolling Interest [Member]	'	'	'	'
Noncontrolling Interest [Line Items]	'	'	'	'
Stockholders' Equity Attributable to Noncontrolling Interest	1,237,115	'	'	1,246,402
Net earnings attributable to noncontrolling interests	49,169	'	'	'
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount	2,491	'	'	'
Amount reclassified out of AOCI, net of tax	185	'	'	'
Foreign currency translation adjustment, Net-of Tax Amount	-2,390	'	'	'
Total other comprehensive income (loss), net of tax	286	'	'	'
Total comprehensive income	49,455	'	'	'
Payments for Repurchase of Common Stock	-45,587	'	'	'
Payments of Dividends	-8,196	'	'	'
Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature	-2,006	'	'	'
Proceeds from Stock Options Exercised	-6,965	'	'	'
Nonredeemable Noncontrolling Interest [Member]	'	'	'	'
Noncontrolling Interest [Line Items]	'	'	'	'
Stockholders' Equity Attributable to Noncontrolling Interest	5,833	'	'	5,887
Net earnings attributable to noncontrolling interests	59	'	'	'
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	-113	'	'	'
Total other comprehensive income (loss), net of tax	-113	'	'	'
Total comprehensive income	-54	'	'	'
Payments for Repurchase of Common Stock	0	'	'	'
Payments of Dividends	0	'	'	'
Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature	0	'	'	'
Proceeds from Stock Options Exercised	0	'	'	'
Stockholders' Equity, Total [Member]	'	'	'	'
Noncontrolling Interest [Line Items]	'	'	'	'
Stockholders' Equity Attributable to Noncontrolling Interest	1,242,948	'	'	1,252,289
Net earnings attributable to noncontrolling interests	49,228	'	'	'
Unrealized gain (loss) on derivative instrument, Net-of-Tax Amount	2,491	'	'	'
Amount reclassified out of AOCI, net of tax	185	'	'	'
Foreign currency translation adjustment, Net-of Tax Amount	-2,503	'	'	'
Total other comprehensive income (loss), net of tax	173	'	'	'
Total comprehensive income	49,401	'	'	'
Payments for Repurchase of Common Stock	-45,587	'	'	'
Payments of Dividends	-8,196	'	'	'
Proceeds from Stock Options Exercised	($6,965)	'	'	'

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Details) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 29, 2014	Mar. 31, 2014
Equity [Abstract]	'	'
Number of shares of common stock purchased	662,598	'
Value of shares of common stock purchased	$45,587	'
Treasury stock, shares	6,983,820	6,321,222

Stockholders_Equity_Redeemable

Stockholders' Equity Redeemable Noncontrolling Interests (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014
Noncontrolling Interest [Abstract]	'
Beginning balance, redeemable noncontrolling interests	$8,047
Net losses attributable to noncontrolling interests	-113
Foreign Currency Translation Adjustments	-54
Ending balance, redeemable noncontrolling interests	$7,880

Earnings_Per_Share_Reconciliat

Earnings Per Share (Reconciliation from Basic to Diluted Average Common Shares) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 29, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]	'	'
Net earnings attributable to EnerSys stockholders	$49,169	$40,847
Basic	46,899,303	47,868,982
Common shares from exercise and lapse of equity awards, net of shares assumed reacquired	1,089,658	829,509
Incremental Common Shares Attributable to Conversion of Debt Securities	1,737,277	606,453
Diluted weighted-average number of common shares outstanding	49,726,238	49,304,944
Basic earnings per common share attributable to EnerSys stockholders	$1.05	$0.85
Diluted earnings per common share attributable to EnerSys stockholders	$0.99	$0.83
Anti-dilutive equity awards not included in diluted weighted-average common shares	414	15,632

Earnings_Per_Share_Additional_

Earnings Per Share (Additional Information) (Details) (USD $)	3 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	31-May-08
Disclosure Earnings Per Share Additional Information [Abstract]	'	'	'
Number of common shares issue upon conversion	4,290,557	'	'
Average Price of Stock	$67.94	'	'
Conversion option price per share	$40.16	'	$40.60
Incremental Common Shares Attributable to Conversion of Debt Securities	1,737,277	606,453	'

Business_Segments_Details

Business Segments (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jun. 29, 2014		Jun. 30, 2013
Segment Reporting Information [Line Items]	'		'
Total net sales	$634,110		$597,297
Net sales revenue by services	634,110		597,297
Total intersegment sales	38,076	[1]	36,101	[1]
Total operating earnings	71,689	[2]	62,608	[2]
Restructuring charges	1,829		421
Reserve Power	'		'
Segment Reporting Information [Line Items]	'		'
Net sales revenue by services	311,374		292,819
Motive Power	'		'
Segment Reporting Information [Line Items]	'		'
Net sales revenue by services	322,736		304,478
Europe	'		'
Segment Reporting Information [Line Items]	'		'
Total net sales	330,928		315,623
Total intersegment sales	8,918		10,093
Total operating earnings	41,489		41,725
Restructuring charges	-1,829		-421
Americas	'		'
Segment Reporting Information [Line Items]	'		'
Total net sales	241,935		230,967
Total intersegment sales	17,699		18,297
Total operating earnings	28,601		16,083
Asia	'		'
Segment Reporting Information [Line Items]	'		'
Total net sales	61,247		50,707
Total intersegment sales	11,459		7,711
Total operating earnings	$3,428		$5,221
[1]	Intersegment sales are presented on a cost-plus basis, which takes into consideration the effect of transfer prices between legal entities.
[2]	The Company does not allocate interest expense or other (income) expense to the reportable segments.

Subsequent_Events_Subsequent_E

Subsequent Events Subsequent Events (Details) (USD $)	3 Months Ended
	Jun. 29, 2014	7-May-14	Aug. 05, 2014
			Subsequent Event [Member]
Investments in New Acquisition [Line Items]	'	'	'
Common Stock, Dividends, Per Share, Declared	$0.18	'	'
Stock Repurchase Program, Authorized Amount	'	$70,000	$60,000