Additional borrowing availability

No definition available.

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- Definition

Future debt expected to be incurred by new capitalized entity

+ References

No definition available.

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- Definition

Interest reserve amount

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Use of portion of debt proceeds

+ References

No definition available.

+ Details

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- Definition

Use of portion of debt proceeds to repay other debt

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Paragraph 28

-Subparagraph (b)

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- Definition

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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-Topic 942

-SubTopic 210

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-Subparagraph (SX 210.9-03.16)

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-Subparagraph (SX 210.7-03.16)

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Period Type:	instant

- Definition

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.

+ References

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

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- Definition

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.

+ References

+ Details

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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-Subparagraph (SX 210.5-02.22)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

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-Topic 944

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.7-03.16)

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+ Details

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)(1)(i)

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+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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Period Type:	duration

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Debt Narrative - Senior Unsecured Notes and Secured Term Loan Facility - Railcar (Details) (USD $)	3 Months Ended		1 Months Ended				0 Months Ended		9 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Jan. 31, 2015	Feb. 28, 2014	Mar. 31, 2014	Jan. 31, 2014	Oct. 01, 2014	Dec. 19, 2014	Sep. 30, 2014	Mar. 27, 2014	Dec. 12, 2012	Dec. 31, 2014	Jun. 23, 2014	Sep. 03, 2014	Sep. 26, 2014	Jun. 25, 2014
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 2,000,000	$ 126,000,000
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				381,000,000
Proceeds from Issuance of Private Placement			626,000,000
Proceeds from (Repayments of) Debt			212,000,000
Railcar Segment [Member] \| NCF I Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt						250,000,000
Railcar Segment [Member] \| NCF II Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt						135,000,000
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										300,000,000
Use of portion of debt proceeds		156,000,000
Railcar Segment [Member] \| Class A-1 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt											110,000,000
Interest rate, long-term debt			2.98%
Use of portion of debt proceeds to repay other debt					256,000,000
Proceeds from Issuance of Private Placement			250,000,000
Railcar Segment [Member] \| Class A-2 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt											106,000,000
Interest rate, long-term debt	3.81%		4.06%
Proceeds from Issuance of Private Placement			376,000,000
Railcar Segment [Member] \| ARI Refinanced Term Loan [Member]
Debt Instrument [Line Items]
Interest reserve amount	17,000,000
Long-term Debt												309,000,000
Proceeds from Issuance of Long-term Debt						316,000,000
Use of portion of debt proceeds to repay other debt						194,000,000
Proceeds from issuance of Long-term debt after proceeds used to refinance prior debt						122,000,000
Railcar Segment [Member] \| ARILL2TermLoan [Domain]
Debt Instrument [Line Items]
Long-term Debt												100,000,000
Proceeds from Issuance of Debt							100,000,000
Railcar Segment [Member] \| ARI 2015 Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt	621,000,000
Railcar Segment [Member] \| Lease Fleet Financings [Member]
Debt Instrument [Line Items]
Pledged assets	495,000,000											277,000,000
Use of portion of debt proceeds		409,000,000
Railcar Segment [Member] \| Citizen Bank Revolver [Member]
Debt Instrument [Line Items]
Line of credit facility								350,000,000
Line of credit facility, outstanding borowings	100,000,000
Senior credit facility, maximum borrowing availability								250,000,000
Additional borrowing availability								100,000,000
Railcar Segment [Member] \| Heartland Bank Term Loan [Member] [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt													12,000,000
Railcar Segment [Member] \| Credit Agricole Term Loan [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt														375,000,000
Railcar Segment [Member] \| Banc of America Leasing & Capital, LLC [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt															47,000,000
Railcar Segment [Member] \| Talmer Bank [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt															15,000,000
Railcar Segment [Member] \| Class 2014 A-1 Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued, long-term debt																175,000,000
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																150,000,000
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												4,000,000
Loss on extinguishment of debt (Note 10) \| Railcar Segment [Member]
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ (2,000,000)								$ (2,000,000)
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%