Car hire earned and remitted to GATX.

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- Definition

Lease agreement date.

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No definition available.

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- Definition

Lease Expiration Extended Date

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No definition available.

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- Definition

Lease expiration month.

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No definition available.

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- Definition

Lease expiration period.

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No definition available.

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- Definition

Lease Renewal Period

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No definition available.

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- Definition

Number of auto carrying railcars.

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No definition available.

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- Definition

Number Of Automobile Carrying Railcars

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No definition available.

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- Definition

Number of gondolas leased.

+ References

No definition available.

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- Definition

Number of gondolas returned.

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No definition available.

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- Definition

Number of mill gondolas.

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No definition available.

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- Definition

Number of open top hoppers.

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No definition available.

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- Definition

Operating lease period.

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No definition available.

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- Definition

Operating Leases Annual Lease Payments

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No definition available.

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- Definition

Percentage of shares issued under agreement with GATX corporation.

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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No definition available.

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-SubTopic 20

-Section 50

-Paragraph 2

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- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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GATX Corporation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended	1 Months Ended
	Dec. 31, 2014 Automobile Millgondolas	Dec. 31, 2013	Dec. 31, 2012 Millgondolas Railcar	Sep. 30, 2014	Mar. 31, 2014	Jun. 30, 2014 Opentop_Hoppers	Jan. 10, 2008 Millgondolas Opentop_Hoppers
Lease Commitments [Line Items]
Number of shares acquired by GATX	4,859,871us-gaap_CommonStockSharesIssued	4,850,014us-gaap_CommonStockSharesIssued					239,523us-gaap_CommonStockSharesIssued
Percentage of shares acquired by GATX							4.99%
Cost of newly-issued shares common stock	$ 2,430us-gaap_CommonStockValue	$ 2,425us-gaap_CommonStockValue					$ 5,500us-gaap_CommonStockValue
Cost per share of newly-issued shares common stock	$ 0.50	$ 0.50					$ 23
Number of mill gondolas	10pwx_NumberOfMillGondolas			52pwx_NumberOfMillGondolas			72pwx_NumberOfMillGondolas
Number of open-top hoppers						75pwx_NumberOfOpentopHoppers	137pwx_NumberOfOpentopHoppers
Number of gondolas returned			20pwx_NumberOfGondolasReturned
Number of auto carrying railcars			200pwx_NumberOfAutoCarryingRailcars
Car-hire earned from other railroads and remitted to GATX	3,700pwx_CarHireEarnedAndRemittedToGatx	3,600pwx_CarHireEarnedAndRemittedToGatx
Lease expiration term	7 years
Lease expiration date	Dec. 31, 2025	Dec. 31, 2023
Number of automobile carrying railcarsu	76pwx_NumberOfAutomobileCarryingRailcars
Lease renewal term	1 year
Operating lease maturity period	Mar. 01, 2014
Number of gondolas entered into per diem lease	8pwx_NumberOfGondolasLeased
Gondolas [Member]
Lease Commitments [Line Items]
Period of operating leases	7 years
Annual rent adjusted	163
Annual rental maturity date	January 2015			December 2019
Rental expense	163	163
Annual lease rate				183
Lease expiration date	Dec. 31, 2014
Lease expiration extended date	2019-12
Locomotive [Member]
Lease Commitments [Line Items]
Cost of lease six-axle EMD SD-60 locomotives					233
Minimum [Member] \| Gondolas [Member]
Lease Commitments [Line Items]
Annual rent	$ 248