Commitments and Contingencies (Details 2) (USD $) In Millions, unless otherwise specified	1 Months Ended
	Sep. 30, 2013 item
Commitments and Contingencies
Deductible per claim for each line of coverage, until claim aggregate is reached	$ 1.0
Deductible per claim, once a policy's claim aggregate is reached per line of coverage	0.5
Deductible under health insurance benefits for qualified individuals	0.1
Vehicular traffic accident
Commitments and Contingencies
Reserve for legal settlements	2.3
L.E. Myers Co | Vehicular traffic accident
Commitments and Contingencies
Compensatory damages	0.7
Punitive damages	3.6
Maximum number of times of compensatory damages for estimated punitive damages	3
Maximum estimated punitive damage awards	2.0
Surety bonds
Commitments and Contingencies
Aggregate original face amount of outstanding bonds issued by the surety	901.1
Estimated remaining cost to complete bonded projects	$ 236.7