Property Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Total, gross	$ 6,666,617	$ 6,705,546
Less allowances for depreciation, depletion and amortization	3,507,432	3,287,367
Total, net	3,159,185	3,418,179
Land and Land Improvements
Property, Plant and Equipment [Line Items]
Total, gross	2,120,999	2,122,350
Building
Property, Plant and Equipment [Line Items]
Total, gross	149,575	163,178
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Total, gross	4,195,165	4,206,870
Leaseholds and Leasehold Improvements
Property, Plant and Equipment [Line Items]
Total, gross	10,546	9,238
Deferred Asset Retirement Costs
Property, Plant and Equipment [Line Items]
Total, gross	129,397	136,289
Construction in Progress
Property, Plant and Equipment [Line Items]
Total, gross	$ 60,935	$ 67,621