Leases (Table Text Block)	9 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Supplemental Balance Sheet Information Related to Leases	As of December 31, 2020     Finance   Operating   Total     (Unaudited)     (In thousands)               Buildings and improvements $ - $ 132,011 $ 132,011 Furniture and equipment   20,966   -   20,966 Rental trailers and other rental equipment   106,961   -   106,961 Rental trucks   1,614,194   -   1,614,194 Right-of-use assets, gross   1,742,121   132,011   1,874,132 Less: Accumulated depreciation   (821,800)   (34,825)   (856,625) Right-of-use assets, net $ 920,321 $ 97,186 $ 1,017,507
Summary of Weighted-average remaining lease terms and Discount rates	Finance   Operating       (Unaudited)   Weighted average remaining lease term (years)   4   14.5   Weighted average discount rate   3.5 % 4.6 %
Components of Lease Expense	Nine Months Ended     December 31, 2020     (Unaudited)     (In thousands)       Operating lease costs $ 22,564       Finance lease cost:     Amortization of ROU assets $ 116,002 Interest on lease liabilities   17,448 Total finance lease cost $ 133,450
Maturities of Lease Liabilities	Finance leases   Operating leases     (Unaudited) Year ending December 31,   (In thousands)           2021 $ 190,770 $ 24,267 2022   144,558   22,367 2023   123,094   21,339 2024   86,571   13,767 2025   48,711   4,809 Thereafter   12,389   63,677 Total lease payments   606,093   150,226 Less: imputed interest   (44,742)   (53,002) Present value of lease liabilities $ 561,351 $ 97,224