Components of Debt (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Total debt	$ 903,680	$ 894,936
Less: Current portion of long-term debt	(226,722)	(116,688)
Total long-term debt	676,958	778,248
Senior Notes - 2007 [Member]
Debt Instrument [Line Items]
Rate	6.40%
Credit facilities	500,000	500,000
Senior Notes - 2007 [Member] \| Minimum
Debt Instrument [Line Items]
Maturities	2017
Senior Notes - 2007 [Member] \| Maximum
Debt Instrument [Line Items]
Maturities	2027
Senior Notes - 2006 [Member]
Debt Instrument [Line Items]
Rate	6.10%
Credit facilities	225,000	225,000
Senior Notes - 2006 [Member] \| Minimum
Debt Instrument [Line Items]
Maturities	2013
Senior Notes - 2006 [Member] \| Maximum
Debt Instrument [Line Items]
Maturities	2016
Credit Facilities [Member]
Debt Instrument [Line Items]
Rate	1.45%
Maturities	2016
Credit facilities	164,890	157,483
Bank Overdrafts And Other [Member]
Debt Instrument [Line Items]
Maturities	2012
Bank overdrafts and other	4,279	1,488
Deferred Realized Gains On Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Deferred realized gains on interest rate swaps	$ 9,511	$ 10,965

Debt instrument maturity.

No definition available.

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Interest rate stated in the contractual debt agreement.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date of debt not otherwise defined (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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