STATEMENTS OF COMPREHENSIVE INCOME AND RETAINED EARNINGS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022		Mar. 31, 2021
Income Statement [Abstract]
Interest and fee income	$ 69.8		$ 77.1
Operating lease and rental revenues	79.9		85.8
Used truck sales and other revenues	7.5		17.3
TOTAL INTEREST AND OTHER REVENUES	157.2		180.2
Interest and other borrowing costs	27.9		36.0
Depreciation and other rental expenses	36.9		81.2
Cost of used truck sales and other expenses	4.8		15.6
Selling, general and administrative expenses	14.9		13.6
Provision for losses on receivables	(2.5)		0.6
TOTAL EXPENSES	82.0		147.0
INCOME BEFORE INCOME TAXES	75.2		33.2
Income taxes	18.4		7.7
NET INCOME	56.8		25.5
COMPREHENSIVE INCOME	76.3		34.8
RETAINED EARNINGS AT BEGINNING OF PERIOD	1,716.8	[1]	1,668.7
RETAINED EARNINGS AT END OF PERIOD	$ 1,673.6		$ 1,594.2

[1] The December 31, 2021 balance sheet has been derived from audited financial statements.