Employee Benefit Plans (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 participant	Dec. 31, 2012	Dec. 31, 2011
Employee Benefits Plans [Line Items]
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent	50.00%
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Dollar Amount	$ 17,500
Defined Contribution Plan, Employer Matching Contribution, Percent	6.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount, Per Eligible Participant	100,000
Defined Contribution Plan, Cost Recognized	4,100,000	2,800,000	300,000
Number of Participants in Non Qualifed Deferred Compensation Plan	49
Deferred Compensation Liability, Current and Noncurrent	23,600,000	24,100,000
Multiemployer Plan, Period Contributions	27,165,000	22,723,000	21,969,000
Multiemployer Plans, Maximum Percent Funded Status for Red Zone	65.00%
Multiemployer Plans, Maxium Percent Funded Status for Yellow and Orange Zone and Minimum Percent for Green Zone	80.00%
Locals 302 and 612 Operating Engineers Employers Retirement Fund [Member]
Employee Benefits Plans [Line Items]
Multiemployer Plan, Period Contributions	3,260,000	2,368,000	2,386,000
Operating Engineers Pension Trust Fund [Member]
Employee Benefits Plans [Line Items]
Multiemployer Plan, Period Contributions	2,768,000	2,285,000	2,099,000
Pension Trust Fund for Operating Engineers Pension Plan [Member]
Employee Benefits Plans [Line Items]
Multiemployer Plan, Period Contributions	8,193,000	8,030,000	7,296,000
Laborers Pension Trust Fund for Northern California [Member] [Member]
Employee Benefits Plans [Line Items]
Multiemployer Plan, Period Contributions	2,500,000	2,320,000	1,950,000
All Other Pension Trust Funds [Member]
Employee Benefits Plans [Line Items]
Multiemployer Plan, Period Contributions	$ 10,444,000	$ 7,720,000	$ 8,238,000