Pensions and Other Benefit Plans - Narrative (Details)	12 Months Ended
	Mar. 31, 2025 USD ($) yr pensionPlan	Mar. 31, 2024 USD ($) pensionPlan	Mar. 31, 2023 USD ($)	Sep. 30, 2024 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	$ 23,634,000	$ 4,984,000	$ 0
Fair value of plan assets	6,342,000
Accrued liabilities	113,907,000	127,973,000
Other liabilities, noncurrent	178,538,000	202,555,000
Charge recorded for contributions to defined contribution plans	6,686,000	6,288,000	5,808,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	96,935,000
Defined benefit plan, expected future employer contributions, next fiscal year	3,778,000
Employer contribution	5,136,000	6,761,000
Defined benefit plan, net periodic benefit cost (credit)	27,030,000	7,945,000	$ 1,964,000
Liability, defined benefit plan, noncurrent	62,675,000	70,552,000
Liability, defined benefit plan, current	$ 3,709,000	3,786,000
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Retirement age | yr	65
Percentage of premium contributed	100.00%
Defined benefit plan, net periodic benefit cost (credit)	$ 144,000
Liability, defined benefit plan	733,000
Liability, defined benefit plan, noncurrent	597,000
Liability, defined benefit plan, current	136,000
Postretirement Benefit Plans | American Association of Retired Persons
Defined Benefit Plan Disclosure [Line Items]
Employer contribution	35
Defined Benefit Postretirement Life Insurance
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, net periodic benefit cost (credit)	32,000
Liability, defined benefit pension plan	2,917,000
Accrued liabilities	2,837,000
Other liabilities, noncurrent	80,000
Cash surrender value of life insurance	$ 2,474,000	$ 2,392,000
United States
Defined Benefit Plan Disclosure [Line Items]
Number of pension plans settled | pensionPlan	1
Plan assets in excess of benefit obligation				$ 6,974,000
Plan assets in excess of benefit obligation, remaining surplus	$ 6,342,000,000
Canada
Defined Benefit Plan Disclosure [Line Items]
Number of pension plans settled | pensionPlan		2