Notes, Loans and Finance Leases Payable, net (Long-term Debt Borrowings) (Details) - USD ($) $ in Thousands	9 Months Ended
Dec. 31, 2024	Mar. 31, 2024
Debt instrument, maturities:
Debt Instrument Carrying Amount	$ 6,444,590	$ 5,850,346
Notes, loans and finance/capital leases payable	6,929,591	6,304,038
Less: Debt issuance costs	(32,604)	(32,676)
Total notes, loans and finance/capital leases payable, net	$ 6,896,987	6,271,362
Real estate loan (amortizing term) [Member]
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	5.42%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2027
Debt instrument, maturity year range, end	2037
Debt Instrument Carrying Amount	$ 268,857	277,767
Real estate loan (amortizing term) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	4.30%
Real estate loan (amortizing term) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.03%
Senior mortgages
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	4.16%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2026
Debt instrument, maturity year range, end	2042
Debt Instrument Carrying Amount	$ 2,167,983	2,284,853
Senior mortgages \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.70%
Senior mortgages \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.05%
Real estate loans (revolving credit) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, end	2027
Fleet loans (amortizing term) [Member]
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	5.12%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2025
Debt instrument, maturity year range, end	2031
Debt Instrument Carrying Amount	$ 120,554	70,454
Fleet loans (amortizing term) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.61%
Fleet loans (amortizing term) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.92%
Fleet loans (revolving credit) [Member]
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	5.81%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2027
Debt instrument, maturity year range, end	2029
Debt Instrument Carrying Amount	$ 615,000	573,889
Fleet loans (revolving credit) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.42%
Fleet loans (revolving credit) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.93%
Capital Leases (rental equipment) [Member]
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	4.34%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2025
Debt instrument, maturity year range, end	2026
Debt Instrument Carrying Amount	$ 56,980	117,641
Capital Leases (rental equipment) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.89%
Capital Leases (rental equipment) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.01%
Finance capital lease [Member]
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	5.03%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2025
Debt instrument, maturity year range, end	2031
Debt Instrument Carrying Amount	$ 1,931,815	1,708,619
Finance capital lease [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.60%
Finance capital lease [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.80%
Private Placement
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	3.62%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2029
Debt instrument, maturity year range, end	2035
Debt Instrument Carrying Amount	$ 1,700,000	1,200,000
Private Placement \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.43%
Private Placement \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.00%
Other obligations
Debt instruments, interest rate, stated percentage:
Debt Weighted Average Interest Rate	6.32%
Debt instrument, maturities:
Debt instrument, maturity year range, start	2025
Debt instrument, maturity year range, end	2049
Debt Instrument Carrying Amount	$ 68,402	$ 70,815
Other obligations \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.50%
Other obligations \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	8.00%

The latest maturity year for these debt instruments.

No definition available.

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- Definition

The earliest maturity year for these debt instruments.

+ References

No definition available.

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- Definition

Amount of accumulated amortization of debt issuance costs classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Topic 210
-Publisher FASB
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-Topic 470
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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- References

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-1A

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-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

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- References

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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