Leases (Table Text Block)	6 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Supplemental Balance Sheet Information Related to Leases	As of September 30, 2020     Finance   Operating   Total     (Unaudited)     (In thousands)               Buildings and improvements $ - $ 131,218 $ 131,218 Furniture and equipment   20,965   -   20,965 Rental trailers and other rental equipment   115,875   -   115,875 Rental trucks   1,637,456   -   1,637,456 Right-of-use assets, gross   1,774,296   131,218   1,905,514 Less: Accumulated depreciation   (803,935)   (29,272)   (833,207) Right-of-use assets, net $ 970,361 $ 101,946 $ 1,072,307
Summary of Weighted-average remaining lease terms and Discount rates	Finance   Operating       (Unaudited)   Weighted average remaining lease term (years)   4   14   Weighted average discount rate   3.5 % 4.6 %
Components of Lease Expense	Six Months Ended     September 30, 2020     (Unaudited)     (In thousands)       Operating lease costs $ 14,540       Finance lease cost:     Amortization of right-of-use assets $ 79,259 Interest on lease liabilities   12,082 Total finance lease cost $ 91,341
Maturities of Lease Liabilities	Finance leases   Operating leases     (Unaudited) Year ending September 30,   (In thousands)           2021 $ 183,067 $ 24,731 2022   143,263   22,413 2023   121,509   21,605 2024   82,967   17,181 2025   60,569   5,717 Thereafter   20,775   64,484 Total lease payments   612,150   156,131 Less: imputed interest   -   (54,155) Present value of lease liabilities $ 612,150 $ 101,976