Railcar Leasing and Management Services Group - Schedule of proceeds from leased railcars (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)
Property Subject to or Available for Operating Lease [Line Items]
Proceeds from sale leased railcars		$ 200.9	$ 85.6
Sales-type Lease, Revenue	$ 32.3	34.2
Payments to Acquire Equipment on Lease		$ 218.4
Railcars Acquired	6,779	6,779
Railcar Leasing and Management Services Group \| Railcars owned one year or less at the time of sale
Property Subject to or Available for Operating Lease [Line Items]
Proceeds from sale leased railcars		$ 101.0	29.2
Railcar Leasing and Management Services Group \| Railcars owned more than one year at the time of sale
Property Subject to or Available for Operating Lease [Line Items]
Proceeds from sale leased railcars		$ 99.9	$ 56.4

Proceeds from Sale of Property Subject to or Available For Operating Lease

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- Definition

Railcars Acquired

+ References

No definition available.

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- Definition

The cash outflow for payments to acquire rented equipment which is recorded as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of sales-type lease revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919372-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=109225645&loc=SL77927221-108306

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