Borrowings - Components of Debt (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Total debt	$ 1,031,175	$ 894,936
Less: Current portion of long-term debt	(150,071)	(116,688)
Total long-term debt	881,104	778,248
Senior Notes - 2007 [Member]
Debt Instrument [Line Items]
Rate	6.40%
Credit facilities	500,000	500,000
Senior Notes - 2007 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Maturities	2017
Senior Notes - 2007 [Member] | Maximum [Member]
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 [Member]
Debt Instrument [Line Items]
Maturities	2013
Senior Notes - 2006 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Maturities	2016
Credit facilities [Member]
Debt Instrument [Line Items]
Rate	1.41%
Maturities	2016
Credit facilities	296,748	157,483
Bank overdrafts and other [Member]
Debt Instrument [Line Items]
Rate	1.20%
Maturities	2012
Bank overdrafts and other	399	1,488
Deferred realized gains on interest rate swaps [Member]
Debt Instrument [Line Items]
Deferred realized gains on interest rate swaps	$ 9,028	$ 10,965