Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Year	Dec. 31, 2010 Year
Finite-Lived Intangible Assets [Line Items]
Historical Cost	$ 56,400	$ 56,400
Accumulated Amortization	(6,652)
Net Balance	49,748	56,400
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Useful Life	9.0	9.0
Historical Cost	50,000	50,000
Accumulated Amortization	(5,682)
Net Balance	44,318	50,000
Tradenames and trademarks
Finite-Lived Intangible Assets [Line Items]
Useful Life	10.0	10.0
Historical Cost	5,300	5,300
Accumulated Amortization	(530)
Net Balance	4,770	5,300
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Useful Life	2.5	2.5
Historical Cost	1,100	1,100
Accumulated Amortization	(440)
Net Balance	$ 660	$ 1,100

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.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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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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- Definition

The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. 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.

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- Definition

The calculated weighted-average useful life of all finite-lived intangible assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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