Commitments, Contingencies and Other Matters - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Commitments and Contingencies Disclosure [Line Items]
Letters of credit, collateral for retrospective premiums and retained losses	$ 40.6
Commitments to purchase major equipment	352
Current obligation	42.5
Obligation for next year	13.5
Self-insured retention	2.0
Workers' compensation and automobile liability insurance coverage, deductible per occurrence	1.0
Non Revolving Senior Secured Term Loan
Commitments and Contingencies Disclosure [Line Items]
Advance to non-affiliates	12.0
Notes receivable interest rate	5.00%
Notes receivable	$ 2.9

Advances to Non Affiliates

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- Definition

Annual Coverage Limit for Workers Compensation and Automobile Liability Insurance Coverages

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- Definition

Notes Receivable Interest Rate

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

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-Article 5

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-Publisher AICPA

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- Definition

Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property.

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- Definition

The floor amount as of the balance sheet date that the entity must expend to satisfy the terms of disclosed arrangements (excluding long-term commitments) in which the entity has agreed to expend funds to procure goods or services from one or more suppliers, other than under a long-term purchase commitment or an unconditional purchase obligation.

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-Article 7

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- Definition

The remaining amount of the fixed and determinable portion of an unrecorded unconditional purchase obligation to be paid within one year of the balance sheet date.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 7

-Subparagraph b

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- Definition

The amount of the fixed and determinable portion of an unrecorded unconditional purchase obligation as of the balance sheet date.

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