Business Segments (Tables)

12 Months Ended

Mar. 31, 2025

Segment Reporting [Abstract]

Summary Of Financial Information Related To The Company's Business Segments

Summarized financial information related to the Company’s reportable segments at March 31, 2025, 2024 and 2023 and for each of the fiscal years then ended is shown below.

	Twelve months ended
	March 31, 2025
	Energy Systems		Motive Power		Specialty		Total
Net Sales by segment to unaffiliated customers	$	1,531,169	$	1,484,117	$	593,488	$	3,608,774
Net sales from corporate and other							8,805
Total Net Sales							$	3,617,579
Less:
Other segment items(4)	$	1,427,963	$	1,251,362	$	556,534	$	3,244,664
Segment income	$	103,206	$	232,755	$	36,954	$	372,915
Less:
Inventory adjustment relating to exit activities	274		—		3,335		3,609
Restructuring and other exit charges	5,994		5,719		2,715		14,428
Loss on assets held for sale	—		4,634		—		4,634
Amortization of intangible assets	23,620		685		7,500		31,805
Acquisition expense	11		11		2,476		2,498
Integration costs	(96)		—		4,086		3,990
Other	673		1,574		110		2,357
Total operating earnings by segment	$	72,730	$	220,132	$	16,732	$	309,594
Corporate and other(3)							$	155,092
Operating earnings(2)							$	464,686

(1)Reportable segments do not record inter-segment revenues and accordingly there are none to report.

(2)The Company does not allocate interest expense or other (income) expense, net, to the reportable segments.

(3)     Corporate and other includes amounts managed on a company-wide basis and not directly allocated to any reportable segments, primarily relating to IRA production tax credits. Also, included are start-up costs for exploration of a new lithium plant as well as start-up operating expenses from the New Ventures operating segment.

(4) Primarily includes cost of sales and operating expenses

	Twelve months ended
	March 31, 2024
	Energy Systems		Motive Power		Specialty		Total
Net Sales by segment to unaffiliated customers	$	1,590,023	$	1,456,181	$	535,667	$	3,581,871
Net sales from corporate and other							—
Total Net Sales							$	3,581,871
Less:
Other segment items(4)	$	1,503,068	$	1,241,531	$	504,301	$	3,248,900
Segment income	$	86,955	$	214,650	$	31,366	$	332,971
Less:
Inventory adjustment relating to exit activities	17,075		—		3,098		20,173
Restructuring and other exit charges	8,840		11,697		7,566		28,103
Impairment of indefinite-lived intangibles	13,619		—		—		13,619
Legal proceedings charge, net	3,705		—		—		3,705
Amortization of intangible assets	24,503		683		2,808		27,994
Acquisition expense	16		185		—		201
Integration costs	420		—		—		420
Other	3,304		847		295		4,446
Total operating earnings by segment	$	15,473	$	201,238	$	17,599	$	234,310
Corporate and other(3)							$	117,260
Operating earnings(2)							$	351,570

(1)Reportable segments do not record inter-segment revenues and accordingly there are none to report.

(2)The Company does not allocate interest expense or other (income) expense, net, to the reportable segments.

(3)     Corporate and other includes amounts managed on a company-wide basis and not directly allocated to any reportable segments, primarily relating to IRA production tax credits. Also, included are start-up costs for exploration of a new lithium plant as well as start-up operating expenses from the New Ventures operating segment.

(4) Primarily includes cost of sales and operating expenses

	Twelve months ended
	March 31, 2023
	Energy Systems		Motive Power		Specialty		Total
Net Sales by segment to unaffiliated customers	$	1,738,195	$	1,451,244	$	519,140	$	3,708,579
Net sales from corporate and other							—
Total Net Sales							$	3,708,579
Less:
Other segment items(4)	$	1,647,795	$	1,271,272	$	478,653	$	3,397,720
Segment income	$	90,400	$	179,972	$	40,487	$	310,859
Less:
Inventory adjustment relating to exit activities	(211)		892		—		681
Restructuring and other exit charges	1,441		12,864		2,134		16,439
Impairment of indefinite-lived intangibles	100		—		380		480
Amortization of intangible assets	27,383		441		2,923		30,747
Acquisition expense	87		317		—		404
Integration costs	138		—		—		138
Other	487		310		95		892
Total operating earnings by segment	$	60,975	$	165,148	$	34,955	$	261,078
Corporate and other(3)							$	17,283
Operating earnings(2)							$	278,361

(1)Reportable segments do not record inter-segment revenues and accordingly there are none to report.

(2)The Company does not allocate interest expense or other (income) expense, net, to the reportable segments.

(3)     Corporate and other includes amounts managed on a company-wide basis and not directly allocated to any reportable segments, primarily relating to IRA production tax credits. Also, included are start-up costs for exploration of a new lithium plant as well as start-up operating expenses from the New Ventures operating segment.

(4) Primarily includes cost of sales and operating expenses

	Fiscal year ended March 31,
	2025		2024		2023
Capital Expenditures
Energy Systems	$	39,167	$	33,626	$	37,249
Motive Power	22,758		17,115		16,373
Specialty	47,016		35,596		35,150
Other	12,097		100		—
Total	$	121,038	$	86,437	$	88,772
Depreciation and Amortization
Energy Systems	$	50,443	$	49,469	$	52,034
Motive Power	23,695		23,690		22,404
Specialty	26,706		18,762		16,715
Other	32		100		—
Total	$	100,876	$	92,021	$	91,153

The Company's property, plant and equipment by reportable segments as of March 31, 2025 and 2024 are as follows:

	March 31, 2025		March 31, 2024
Property, plant and equipment, net
Energy Systems	$	198,841	$	189,519
Motive Power	144,076		145,395
Specialty	236,861		197,368
Other	12,655		168
Total	$	592,433	$	532,450