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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Average fixed interest rate related to the group of interest rate derivatives.

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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.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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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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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Derivative Instruments and Fair Value Accounting Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 2,529.6	$ 2,565.1	$ 2,562.0	$ 4,671.8	$ 4,834.6	$ 4,858.0
Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2006 Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 200.0
Derivative, Average Fixed Interest Rate	4.87%
Derivative Liability	$ 0.0
Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2018 Secured Railcar Equipment Notes [Domain]
Derivative [Line Items]
Derivative, Notional Amount	$ 249.3
Derivative, Average Fixed Interest Rate	4.41%
Derivative Liability	$ 0.0
Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, TRIP Holdings Warehouse Loan [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 788.5
Derivative, Average Fixed Interest Rate	3.60%
Derivative Liability	$ 0.0
Designated as Hedging Instrument [Member] \| Interest Rate Swap, Open, TRIP Master Funding Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 34.8
Derivative, Average Fixed Interest Rate	2.62%
Derivative Liability	$ 0.0
Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 169.3
Derivative, Cap Interest Rate	3.00%
Derivative Liability	$ 0.0
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 586.2
Derivative, Cap Interest Rate	2.68%
Derivative Liability	$ (29.2)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(20.5)		$ (8.3)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2006 Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(0.2)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2018 Secured Railcar Equipment Notes [Domain]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1.2
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, TRIP Holdings Warehouse Loan [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	2.6
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Open, TRIP Master Funding Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.2
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(0.7)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	29.2
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2006 Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.0
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, 2018 Secured Railcar Equipment Notes [Domain]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.0
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Expired, TRIP Holdings Warehouse Loan [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	3.6
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap, Open, TRIP Master Funding Secured Railcar Equipment Notes [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.2
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.0
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 0.0