Amortizable Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Finite-Lived Intangible Assets [Line Items]
Noncompetition and other agreements	$ 335,012	$ 309,405
Lease agreements	8,081	8,466
Deferred debt financing costs	66,011	61,405
Finite-Lived Intangible Assets, Gross, Total	409,104	379,276
Less accumulated amortization	(249,613)	(216,641)
Total amortizable intangible assets	$ 159,491	$ 162,635

For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

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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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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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.

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Gross carrying amount before accumulated amortization as of the balance sheet date of payments made to third parties in exchange for their agreement not to engage in specified competitive practices in specified geographic territories for a specified period of time.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Gross carrying amount before accumulated amortization as of the balance sheet date of intangible assets not otherwise specified in the taxonomy having a reasonably expected period of economic benefit.

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