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Future debt expected to be incurred by new capitalized entity

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Interest reserve amount

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Proceeds from issuance of Long-term debt after proceeds used to refinance prior debt

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Use of portion of debt proceeds

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Use of portion of debt proceeds to repay other debt

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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

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No definition available.

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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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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 carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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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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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

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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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No definition available.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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The net cash inflow or outflow in aggregate debt due to repayments and proceeds from additional borrowings.

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Debt Narrative - Senior Unsecured Notes and Secured Term Loan Facility - Railcar (Details) - Credit Facility [Domain] - USD ($) $ in Millions			1 Months Ended				3 Months Ended	6 Months Ended		9 Months Ended
	Dec. 19, 2014	Oct. 01, 2014	Jan. 31, 2015	Mar. 31, 2014	Feb. 28, 2014	Jan. 31, 2014	Mar. 31, 2014	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Sep. 26, 2014	Sep. 03, 2014	Jun. 25, 2014	Jun. 23, 2014	Mar. 27, 2014	Dec. 12, 2012
Debt Instrument [Line Items]
Loss on extinguishment of debt								$ 2	$ 162
Railcar Segment [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)			5.00%
Future debt expected to be incurred by new capitalized entity					$ 381
Proceeds from Issuance of Private Placement			$ 626
Proceeds from (Repayments of) Debt			$ 212
Railcar Segment [Member] \| NCF I Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt						$ 250
Railcar Segment [Member] \| NCF II Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt						$ 135
Interest rate, long-term debt						3.70%
Railcar Segment [Member] \| RCF Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt																$ 300
Use of portion of debt proceeds							$ 156
Railcar Segment [Member] \| Class A-1 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt																	$ 110
Interest rate, long-term debt			2.98%
Use of portion of debt proceeds to repay other debt				$ 256
Proceeds from Issuance of Private Placement			$ 250
Railcar Segment [Member] \| Class A-2 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt																	$ 106
Interest rate, long-term debt			4.06%					3.81%
Proceeds from Issuance of Private Placement			$ 376
Railcar Segment [Member] \| ARI Refinanced Term Loan [Member]
Debt Instrument [Line Items]
Interest reserve amount								$ 17
Long-term Debt											$ 309
Proceeds from Issuance of Long-term Debt						$ 316
Use of portion of debt proceeds to repay other debt						194
Proceeds from issuance of Long-term debt after proceeds used to refinance prior debt						$ 122
Railcar Segment [Member] \| ARILL2TermLoan [Domain]
Debt Instrument [Line Items]
Long-term Debt											100
Proceeds from Issuance of Debt		$ 100
Railcar Segment [Member] \| ARI 2015 Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt								621
Railcar Segment [Member] \| Lease Fleet Financings [Member]
Debt Instrument [Line Items]
Pledged assets								490			277
Use of portion of debt proceeds								409
Railcar Segment [Member] \| Citizen Bank Revolver [Member]
Debt Instrument [Line Items]
Line of credit facility	$ 350
Line of credit facility, outstanding borowings								100
Senior credit facility, maximum borrowing availability	250
Additional borrowing availability	$ 100
Railcar Segment [Member] \| Heartland Bank Term Loan [Member] [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt															$ 12
Railcar Segment [Member] \| Credit Agricole Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt													$ 375
Railcar Segment [Member] \| Banc of America Leasing & Capital, LLC [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt												$ 47
Railcar Segment [Member] \| Talmer Bank [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt												$ 15
Railcar Segment [Member] \| Class 2014 A-1 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt														$ 175
Interest rate, long-term debt														2.92%
Railcar Segment [Member] \| Class 2014 A-2 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt														$ 150
Interest rate, long-term debt														3.97%
Railcar Segment [Member] \| Term Loan [Member] \| ARI Notes due 2020 [Member]
Debt Instrument [Line Items]
Interest reserve amount											$ 4
Loss on extinguishment of debt (Note 10) \| Railcar Segment [Member]
Debt Instrument [Line Items]
Loss on extinguishment of debt								$ (2)		$ (2)
Minimum [Member] \| Railcar Segment [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Interest rate, long-term debt								3.35%
Maximum [Member] \| Railcar Segment [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Interest rate, long-term debt								6.95%
LIBOR [Member] \| Railcar Segment [Member] \| NCF I Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								2.00%
LIBOR [Member] \| Railcar Segment [Member] \| Class A-1 Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								1.75%
LIBOR [Member] \| Railcar Segment [Member] \| Citizen Bank Revolver [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								1.45%
LIBOR [Member] \| Railcar Segment [Member] \| Credit Agricole Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								1.75%
LIBOR [Member] \| Railcar Segment [Member] \| Banc of America Leasing & Capital, LLC [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								1.75%
LIBOR [Member] \| Railcar Segment [Member] \| Talmer Bank [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								1.50%