The effective interest rate at the end of the reporting period.

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-SubTopic 30

-Section 45

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Interest rate stated in the contractual debt agreement.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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-Name Statement of Financial Accounting Standard (FAS)

-Number 129

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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Long Term Debt (Parenthetical) (Detail)	3 Months Ended	6 Months Ended
Long Term Debt (Parenthetical) (Detail)	Jun. 30, 2012 6.6% Senior Notes, due 2018	Jun. 30, 2012 6.6% Senior Notes, due 2018	Jun. 30, 2012 7% Debentures, Due 2025	Jun. 30, 2012 6.25% Senior Notes, Due 2037	Jun. 30, 2012 Term Loan Facility, Due 2015	Dec. 31, 2011 Term Loan Facility, Due 2015	Jun. 30, 2011 Term Loan Facility, Due 2015	Jun. 30, 2012 Revolving Facility	Dec. 31, 2011 Revolving Facility	Jun. 30, 2011 Revolving Facility	Jun. 30, 2012 AR Credit Facility	Dec. 31, 2011 AR Credit Facility	Jun. 30, 2011 AR Credit Facility
Debt Instrument
Maturity date	2018	2018	2025	2037	2015
Interest rate on notes	6.60%	6.60%	7.00%	6.25%
Interest rate on term loan					1.87%	2.20%	1.87%
Credit Facility interest rate								1.62%	2.64%	1.56%	1.00%	1.66%	1.60%