Supplemental Cash Flow and Noncash Investing Transactions (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) Car	Dec. 31, 2016 USD ($)
Noncash or Part Noncash Divestitures [Line Items]
Noncash or Part Noncash Acquisition, Debt Assumed	$ 0.0	$ 11.6	$ 0.0
Number of railcars received \| Car		1,224
Supplemental Cash Flow Information
Interest paid	164.0	$ 154.6	145.4
Income taxes paid (refunded), net	18.1	21.5	28.6
Portfolio proceeds	$ 234.4	$ 165.6	$ 223.7

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Portfolio proceeds.

+ References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to 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; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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- Definition

The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 230
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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