Leases (Components of our right-of-use assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Mar. 31, 2022
Finance Lease [Abstract]
Buildings and Improvements	$ 142,748	$ 136,444
Furniture and equipment	14,731	14,731
Rental trailers and other rental equipment	152,867	169,514
Rental trucks	982,119	1,114,248
Right-of-use assets, gross	1,292,465	1,434,937
Less: Accumulated depreciation	(723,969)	(739,731)
Right of use assets, net	568,496	695,206
Finance Lease [Member]
Finance Lease [Abstract]
Buildings and Improvements	0	0
Furniture and equipment	14,731	14,731
Rental trailers and other rental equipment	152,867	169,514
Rental trucks	982,119	1,114,248
Right-of-use assets, gross	1,149,717	1,298,493
Less: Accumulated depreciation	(645,077)	(677,669)
Right of use assets, net	504,640	620,824
Operating Lease [Member]
Finance Lease [Abstract]
Buildings and Improvements	142,748	136,444
Furniture and equipment	0	0
Rental trailers and other rental equipment	0	0
Rental trucks	0	0
Right-of-use assets, gross	142,748	136,444
Less: Accumulated depreciation	(78,892)	(62,062)
Right of use assets, net	$ 63,856	$ 74,382