Intangible Assets (Detail) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets, net (excluding goodwill)	$ 22,792	$ 25,874
Amortization	(3,082)
Noncompete Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	1,400	1,400
Accumulated amortization	(466)	(116)
Intangible assets, net (excluding goodwill)	934	1,284
Amortization	(350)
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	25,500	25,500
Accumulated amortization	(3,642)	(910)
Intangible assets, net (excluding goodwill)	21,858	24,590
Amortization	$ (2,732)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

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Aggregate amount of intangible asset amortization recognized as expense during the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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