Entity Wide Accounts Receivable Major Customer Percentage

No definition available.

Name:	arii_EntityWideAccountsReceivableMajorCustomerPercentage
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Period Type:	instant

- Definition

Number of Customers that Made Up More than Ten Percent of Consolidated Accounts Receivable

+ References

No definition available.

+ Details

Name:	arii_NumberofCustomersthatMadeUpMorethanTenPercentofConsolidatedAccountsReceivable
Namespace Prefix:	arii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of Customers that Made Up More than Ten Percent of Consolidated Revenues

+ References

No definition available.

+ Details

Name:	arii_NumberofCustomersthatMadeUpMorethanTenPercentofConsolidatedRevenues
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Balance Type:	na
Period Type:	duration

- Definition

Percentage of assets to consolidated.

+ References

No definition available.

+ Details

Name:	arii_PercentageOfAssetsToConsolidated
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Balance Type:	na
Period Type:	instant

- Definition

Percentage of revenue from affiliates.

+ References

No definition available.

+ Details

Name:	arii_PercentageOfRevenueFromAffiliates
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Balance Type:	na
Period Type:	duration

- Definition

The percentage of net product revenue to total net revenue from the sale of goods and services as of year end.

+ References

No definition available.

+ Details

Name:	arii_SalesRevenueNetPercentage
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Data Type:	num:percentItemType
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- Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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Operating Segments and Sales, Geographic and Credit Concentrations (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 Segment	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue, Net	$ 150,540us-gaap_SalesRevenueNet	$ 162,842us-gaap_SalesRevenueNet	$ 237,509us-gaap_SalesRevenueNet	$ 182,115us-gaap_SalesRevenueNet	$ 197,179us-gaap_SalesRevenueNet	$ 198,899us-gaap_SalesRevenueNet	$ 159,404us-gaap_SalesRevenueNet	$ 195,110us-gaap_SalesRevenueNet	$ 733,006us-gaap_SalesRevenueNet	$ 750,592us-gaap_SalesRevenueNet	$ 711,723us-gaap_SalesRevenueNet
Number of reportable segments									3us-gaap_NumberOfReportableSegments
Foreign Operations [Member]
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from company's foreign operations									4.20%	2.00%	0.90%
Percentage of foreign assets of the total consolidated assets	1.00%				1.50%				1.00%	1.50%
Sales Revenue, Segment [Member] \| IELP Entities [Member]
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from significant customer									31.00%	31.70%	14.50%
Sales Revenue, Segment [Member] \| CIT Group, Inc [Member]
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from significant customer									11.90%	24.40%	49.40%
Railcar Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue, Net									67,842	72,854	65,227
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from affiliates									2.60%	2.30%	3.00%
Number of customers that made up more than 10% of consolidated revenues									0	0	0
Number of customers that made up more than 10% of consolidated accounts receivable	0				0				0	0
Railcar Leasing [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue, Net									$ 65,108	$ 31,871	$ 13,444
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from affiliates									0.00%	0.00%	0.00%
Number of customers that made up more than 10% of consolidated revenues									0	0	0
Number of customers that made up more than 10% of consolidated accounts receivable	0				0				0	0
Operating Segments [Member]
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Percentage of revenue from affiliates									33.50%	33.40%	14.50%
Operating Segments [Member] \| Accounts Receivable [Member]
Operating Segment and Sales and Credit Concentrations (Textual) [Abstract]
Manufacturing receivables from significant customers	60.50%				22.60%				60.50%	22.60%