Borrowings (Long-term Debt Borrowings) (Details) - USD ($) $ in Thousands	9 Months Ended
	Dec. 31, 2020	Mar. 31, 2020
Debt instrument, maturities:
Notes, loans and finance/capital leases payable	$ 4,708,458	$ 4,651,068
Less: Debt issuance costs	(30,231)	(29,777)
Total notes, loans and finance/capital leases payable, net	$ 4,678,227	$ 4,621,291
Real estate loan (amortizing term) [Member]
Debt instrument, maturities:
Debt instrument, maturity year	2023
Real estate loan (amortizing term) [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.65%
Senior Mortgages [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2021
Debt instrument, maturity year range, end	2038
Senior Mortgages [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.80%
Senior Mortgages [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	6.62%
Real estate loans (revolving credit) [Member]
Debt instrument, maturities:
Debt instrument, maturity year	2025
Debt instrument, maturity year range, start	2022
Real estate loans (revolving credit) [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.55%
Real estate loans (revolving credit) [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	3.25%
Fleet loans (amortizing term) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2021
Debt instrument, maturity year range, end	2027
Fleet loans (amortizing term) [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.04%
Fleet loans (amortizing term) [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	4.66%
Fleet loans (revolving credit) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2022
Debt instrument, maturity year range, end	2024
Fleet loans (revolving credit) [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage
Fleet loans (revolving credit) [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.30%
Capital Leases (rental equipment) [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2021
Debt instrument, maturity year range, end	2026
Capital Leases (rental equipment) [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	1.92%
Capital Leases (rental equipment) [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	5.04%
Finance capital lease [Member]
Debt instrument, maturities:
Debt instrument, maturity year	2028
Debt instrument, maturity year range, start	2024
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	4.22%
Other Obligations [Member]
Debt instrument, maturities:
Debt instrument, maturity year range, start	2021
Debt instrument, maturity year range, end	2049
Other Obligations [Member] | Minimum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	2.50%
Other Obligations [Member] | Maximum [Member]
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage	8.00%