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Repayments on Warehouse Loan Facility

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Weighted average interest rate of debt outstanding.

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Debt - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 250.0		$ 250.0
Gain (Loss) on Extinguishment of Debt	$ 0.0	$ 0.0	$ (11.7)	$ (5.0)
Corporate Segment [Member] \| Senior Notes [Member] \| 4.55% Senior Notes Due October 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.55%		4.55%
Corporate Segment [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 450.0		$ 450.0
Proceeds from Lines of Credit			470.0
Repayments of Lines of Credit			520.0
Line of Credit Facility, Current Borrowing Capacity	$ 421.7		$ 421.7
Debt Instrument, Interest Rate, Effective Percentage	1.75%		1.75%
Line of Credit Facility, Interest Rate at Period End	0.25%		0.25%
Corporate Segment [Member] \| Letter of Credit [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount	$ 28.3		$ 28.3
TILC [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRL-2021 Series 2021-1 Class A Green Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.26%		2.26%
Debt Instrument, Face Amount	$ 305.2		$ 305.2
TILC [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRL-2021 Series 2021-1 Class B Green Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.08%		3.08%
Debt Instrument, Face Amount	$ 19.8		$ 19.8
TILC [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRL-2021 Series 2021-1Green Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Payments of Debt Issuance Costs			3.3
Proceeds from Issuance of Debt			$ 214.4
TILC [Member] \| Railcar Leasing and Management Services Group [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member] \| TILC Warehouse Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	1.94%		1.94%
Debt Instrument, Face Amount	$ 1,000.0		$ 1,000.0		$ 750.0
Borrowings on Warehouse Loan Facility			374.7
Repayments on Warehouse Loan Facility			379.7
Line of Credit Facility, Remaining Borrowing Capacity Exclusive of Current Restrictions	$ 485.6		485.6
TRIP Holdings [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRIP Master Funding Secured Railcar Equipment Notes [Member]
Debt Instrument [Line Items]
Payments of Debt Issuance Costs			5.6
Extinguishment of Debt, Amount			869.1
Gain (Loss) on Extinguishment of Debt			8.7
Write off of Deferred Debt Issuance Cost			5.4
Payment for Debt Extinguishment or Debt Prepayment Cost			$ 3.3
Debt, Weighted Average Interest Rate	5.16%		5.16%
TRIP Holdings [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| Triumph Rail Class A Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.15%		2.15%
Debt Instrument, Face Amount	$ 535.0		$ 535.0
TRIP Holdings [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| Triumph Rail Class B Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.08%		3.08%
Debt Instrument, Face Amount	$ 25.4		$ 25.4
TRIP Holdings [Member] \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRIP Railcar Co Term Loan
Debt Instrument [Line Items]
Proceeds from Lines of Credit			$ 329.6
Debt Instrument, Interest Rate, Effective Percentage	1.94%		1.94%
Payments of Debt Issuance Costs			$ 2.9
Debt Instrument, Interest Rate, Increase (Decrease)			1.85%
RIV 2013 Holdings \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRP-2021 Class A Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.07%		2.07%
Debt Instrument, Face Amount	$ 334.0		$ 334.0
RIV 2013 Holdings \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRP 2021 Class B Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.06%		3.06%
Debt Instrument, Face Amount	$ 21.0		$ 21.0
RIV 2013 Holdings \| Railcar Leasing and Management Services Group [Member] \| Secured Debt [Member] \| TRL 2012 Secured Railcar Equipment Notes - RIV 2013 [Member]
Debt Instrument [Line Items]
Payments of Debt Issuance Costs			3.7
Extinguishment of Debt, Amount			348.0
Write off of Deferred Debt Issuance Cost			$ 3.0
Debt, Weighted Average Interest Rate	3.59%		3.59%
Minimum \| Corporate Segment [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	0.30%		0.30%
Line of Credit Facility, Interest Rate at Period End	0.175%		0.175%
Maximum \| Corporate Segment [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	0.40%		0.40%