Borrowings (Long-term debt borrowings) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Debt instrument, maturities:
Notes, loans and leases payable, gross	$ 5,710,735	$ 5,875,781
Notes, loans and finance/capital leases payable	6,143,350	6,059,713
Less: Debt issuance costs	(35,308)	(37,216)
Notes, loans and finance/capital leases payable, net	$ 6,108,042	6,022,497
Real estate loan (amortizing term) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2027
Debt instrument, maturity year range, end	2037
Notes, loans and finance/capital leases payable	$ 289,647	50,259
Real estate loan (amortizing term) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	4.29%
Real estate loan (amortizing term) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.14%
Senior mortgages [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2024
Debt instrument, maturity year range, end	2042
Notes, loans and finance/capital leases payable	$ 2,371,231	2,206,268
Senior mortgages [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.70%
Senior mortgages [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.50%
Real estate loans (revolving credit) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, end	2027
Notes, loans and finance/capital leases payable	$ 0	535,000
Real estate loans (revolving credit) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	0.00%
Real estate loans (revolving credit) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	0.00%
Fleet loans (amortizing) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2023
Debt instrument, maturity year range, end	2029
Notes, loans and finance/capital leases payable	$ 111,856	124,651
Fleet loans (amortizing) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.61%
Fleet loans (amortizing) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.68%
Fleet loans (securitization) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2025
Debt instrument, maturity year range, end	2027
Notes, loans and finance/capital leases payable	$ 615,000	560,000
Fleet loans (securitization) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.36%
Fleet loans (securitization) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.97%
Fleet Loans (revolving credit) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2023
Debt instrument, maturity year range, end	2026
Notes, loans and finance/capital leases payable	$ 223,205	347,393
Fleet Loans (revolving credit) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.18%
Fleet Loans (revolving credit) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.04%
Capital leases (rental equipment) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2024
Debt instrument, maturity year range, end	2031
Notes, loans and finance/capital leases payable	$ 1,255,763	949,936
Capital leases (rental equipment) [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.60%
Capital leases (rental equipment) [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.98%
Private placements [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2029
Debt instrument, maturity year range, end	2035
Notes, loans and finance/capital leases payable	$ 1,200,000	1,200,000
Private placements [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.43%
Private placements [Member] \| Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.88%
Other Obligations [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2023
Debt instrument, maturity year range, end	2049
Notes, loans and finance/capital leases payable	$ 76,648	$ 86,206
Other Obligations [Member] \| Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.50%
Other Obligations [Member] \| 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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The earliest maturity year for these debt instruments.

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

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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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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