Schedule Of Principal Payments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
2013
2014
2015
2016	655,000
2017	465,000
Thereafter
Total principal payments	1,120,000
Unamortized bond discount	(8,455)
Total debt	$ 1,111,545	$ 1,245,014

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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