Components of Interest Expense (Detail) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Component of Other Expense, Nonoperating [Line Items]
Interest on borrowings and related fees	$ 13,581	$ 10,758	$ 37,448	$ 32,245
Accretion on original issue discount	315	1,986	3,103	6,097
Amortization of debt issuance costs	747	883	2,709	2,992
Capitalized interest	(437)	(438)	(1,427)	(1,155)
Other, net		9		11
Interest expense	$ 14,206	$ 13,198	$ 41,833	$ 40,190

The component of interest expense representing the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate caption: Noncash Interest Expense.

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The component of interest expense comprised of the periodic charge against earnings over the life of the financing arrangement to which such costs relate. Alternate captions include Noncash Interest Expense.

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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 cost of borrowed funds accounted for as interest that was charged against earnings during the period.

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Aggregate amount of interest expense on all borrowings.

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Interest expense on all other items not previously classified. For example, includes dividends associated with redeemable preferred stock of a subsidiary that is treated as a liability in the parent's consolidated balance sheet.

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The amount of cash paid during the current period for interest that is capitalized.

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