Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

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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

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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- Definition

Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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Derivative Instruments - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	May 31, 2018	Jul. 31, 2011	Dec. 31, 2006
Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative [Line Items]
Expected effect during next twelve months	$ 2.0
TRIP Master Funding secured railcar equipment notes
Derivative [Line Items]
Expected effect during next twelve months	0.2
Interest rate swap, Expired, 2018 secured railcar equipment notes
Derivative [Line Items]
Expected effect during next twelve months	0.2
Designated as hedging instrument \| Interest rate swap, Expired, 2006 secured railcar equipment notes
Derivative [Line Items]
Notional amount	200.0			$ 200.0
Changes in fair value of cash flow hedges which is being amortized to income (loss)	4.5
Designated as hedging instrument \| Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative [Line Items]
Notional amount	788.5
Designated as hedging instrument \| TRIP Master Funding secured railcar equipment notes
Derivative [Line Items]
Notional amount			$ 94.1
Designated as hedging instrument \| Interest rate cap, Open, 2017 promissory note
Derivative [Line Items]
Notional amount	$ 169.3
Libor plus margin for 2017 promissory note	3.00%
Derivative asset	$ 3.0
Designated as hedging instrument \| Interest rate swap, Expired, 2018 secured railcar equipment notes
Derivative [Line Items]
Notional amount	$ 249.3	$ 1.4