Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Debt Instrument [Line Items]
Long-term debt	$ 1,911,795	$ 1,376,259	$ 1,443,002
Less current portion	331,008	87,776	520,285
Long-term debt, noncurrent	1,580,787	1,288,483	922,717
7 1/4% Senior Notes
Debt Instrument [Line Items]
Long-term debt	245,454	245,237	244,612
Less current portion	245,500
5% Senior Notes
Debt Instrument [Line Items]
Long-term debt	500,000
Bank debt
Debt Instrument [Line Items]
Long-term debt	1,166,341	1,131,022	1,198,390
Bank debt | Revolving loans
Debt Instrument [Line Items]
Long-term debt			440,163
Bank debt | U.S. term loans
Debt Instrument [Line Items]
Long-term debt	520,000	520,000	400,000
Bank debt | Canadian term loans
Debt Instrument [Line Items]
Long-term debt	80,943	79,323	83,130
Bank debt | Euro term loans
Debt Instrument [Line Items]
Long-term debt	444,713	433,825	176,413
Bank debt | Other foreign bank revolving and term loans
Debt Instrument [Line Items]
Long-term debt	$ 120,685	$ 97,874	$ 98,684