Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Debt Instrument [Line Items]
Long-term debt	$ 1,783,649	$ 1,671,316	$ 1,911,795
Less current portion	526,059	255,349	331,008
Long-term debt, noncurrent	1,257,590	1,415,967	1,580,787
5% Senior Notes
Debt Instrument [Line Items]
Long-term debt	500,000	500,000	500,000
7 1/4% Senior Notes
Debt Instrument [Line Items]
Long-term debt			245,454
Bank debt
Debt Instrument [Line Items]
Long-term debt	1,283,649	1,171,316	1,166,341
Bank debt | Revolving loans
Debt Instrument [Line Items]
Long-term debt	424,841
Less current portion	424,800
Bank debt | U.S. term loans
Debt Instrument [Line Items]
Long-term debt	364,000	520,000	520,000
Bank debt | Canadian term loans
Debt Instrument [Line Items]
Long-term debt	67,755	81,389	80,943
Bank debt | Euro term loans
Debt Instrument [Line Items]
Long-term debt	300,535	443,406	444,713
Bank debt | Other foreign bank revolving and term loans
Debt Instrument [Line Items]
Long-term debt	126,518	126,521	120,685
Less current portion	$ 101,300