Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	2 Months Ended	9 Months Ended	21 Months Ended
Sep. 30, 2013 case	Sep. 30, 2013	Sep. 30, 2013
Commitments and Contingencies.
Number of heavy equipment statutes cases tried and completed to which the entity is a party	1
Number of heavy equipment statutes cases tried and completed in Texas state district court	2
Ad valorem tax benefit		$ 4.6	$ 8.9
Ad valorem tax benefit agreed to by a number of appraisal review boards and county appraisal districts	2.1	2.1	2.1
Ad valorem tax benefit in litigation	$ 6.8	$ 6.8	$ 6.8

The amount of ad valorem tax expense (benefit) included as a component of cost of goods sold (excluding depreciation and amortization).

No definition available.

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The amount of ad valorem tax expense (benefit) agreed to by one or more appraisal review boards and/or county appraisal districts.

No definition available.

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The amount of ad valorem tax expense (benefit) in litigation in various courts.

No definition available.

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Represents the number of heavy equipment statutes cases tried and completed.

No definition available.

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Represents the number of heavy equipment statutes cases tried and completed to which the entity is a party.

No definition available.

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