Supplemental Cash Flow and Noncash Investing Transactions (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) tankContainer	Dec. 31, 2021 USD ($) tankContainer
Noncash or Part Noncash Divestitures [Line Items]
Number of railcars received \| tankContainer		21	2,329
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 0.8	$ 40.0
Supplemental Cash Flow Information
Interest Paid, Excluding Capitalized Interest, Operating Activities	260.1	202.7	$ 196.6
Income taxes paid (refunded), net	17.3	18.7	10.3
Portfolio proceeds	$ 272.8	$ 269.6	$ 187.1

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Portfolio proceeds.

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- Definition

Fair value portion of assets classified as held for sale.

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- Definition

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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