Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Federal:
Current	$ 11,136,000	$ (2,330,000)	$ 10,288,000
Deferred	7,914,000	(36,519,000)	22,574,000
Total federal	19,050,000	(38,849,000)	32,862,000
State:
Current	2,952,000	(1,071,000)	5,381,000
Deferred	1,346,000	(4,008,000)	407,000
Total state	4,298,000	(5,079,000)	5,788,000
Total provision for (benefit from) income taxes	23,348,000	(43,928,000)	38,650,000
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Federal statutory tax	31,301,000	(37,232,000)	48,598,000
State taxes, net of federal tax benefit	3,497,000	(4,500,000)	3,978,000
Percentage depletion deduction	(1,254,000)	(997,000)	(1,717,000)
Domestic production deduction	(1,604,000)	100,000	(765,000)
Noncontrolling interests	(5,223,000)	1,213,000	(9,345,000)
Settlements and effective settlements of audit issues	(2,348,000)	330,000	0
Other	(1,021,000)	(2,842,000)	(2,099,000)
Total provision for (benefit from) income taxes	23,348,000	(43,928,000)	38,650,000
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Federal statuory tax, Percent	35.00%	35.00%	35.00%
State taxes, net of federal tax benefit, Percent	3.90%	4.20%	2.70%
Percentage depletion deduction, Percent	(1.40%)	0.90%	(1.20%)
Domestic production deduction, Percent	(1.80%)	(0.10%)	(0.60%)
Noncontrolling interests, Percent	(5.80%)	(1.10%)	(6.70%)
Settlements and effective settlements of audit issues, Percent	(2.60%)	(0.30%)	0.00%
Other, Percent	(1.20%)	2.70%	(1.40%)
Total, Percent	26.10%	41.30%	27.80%
Deferred tax assets:
Receivables	2,929,000	3,145,000
Inventory	6,308,000	7,780,000
Insurance	7,142,000	3,775,000
Deferred compensation	16,485,000	19,848,000
Other accrued liabilities	9,244,000	9,888,000
Contract income recognition	4,253,000	15,679,000
Impairments on real estate investments	18,895,000	27,304,000
Other	4,906,000	1,145,000
Net operating loss carryforward	9,510,000	10,477,000
Valuation allowance	(10,668,000)	(13,111,000)	(13,018,000)
Total deferred tax assets	69,004,000	85,930,000
Deferred tax liabilities:
Property and equipment	34,467,000	42,827,000
Total deferred tax liabilities	34,467,000	42,827,000
Net deferred tax assets	34,537,000	43,103,000
Deferred Tax Assets (Liabilities), Net [Abstract]
Current deferred tax assets, net	38,571,000	53,877,000
Long-term deferred tax liabilities, net	4,034,000	10,774,000
Net deferred tax assets	34,537,000	43,103,000
Deferred Tax Assets, Valuation Allowance [Roll Forward]
Beginning balance	13,111,000	13,018,000	11,649,000
Deductions (additions)	(2,443,000)	93,000	1,369,000
Ending balance	10,668,000	13,111,000	13,018,000
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	6,300,000
Ending balance	3,100,000	6,300,000
Unrecognized Tax Benefits	3,100,000	6,300,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	1,100,000	5,000,000
Unrecognized Tax Benefits, Interest on Income Taxes Expense	100,000	(400,000)	700,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	800,000	700,000
Other Long Term Liabilities [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	5,650,000	5,882,000	3,888,000
Gross increases – current period tax positions	1,726,000	180,000	1,107,000
Gross decreases – current period tax positions	(1,420,000)	(453,000)	(1,851,000)
Gross increases – prior period tax positions	1,485,000	4,009,000	3,537,000
Gross decreases – prior period tax positions	(1,467,000)	(1,641,000)	(677,000)
Settlements with taxing authorities/lapse of statute of limitations	(3,635,000)	(2,327,000)	(122,000)
Ending balance	2,339,000	5,650,000	5,882,000
Unrecognized Tax Benefits	2,339,000	5,650,000	5,882,000
Internal Revenue Service (IRS) [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities	$ 3,300,000