Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Large-deductible workers' compensation insurance program | Maximum
Insurance Programs
Insurance program, Company's risk per incident	$ 400
Self-insured employee health program
Insurance Programs
Insurance program, Company's risk per individual covered life	300
D&O coverage | Minimum
Insurance Programs
Insurance program, Company's risk per claim	100
D&O coverage | Maximum
Insurance Programs
Insurance program, Company's risk per claim	250
Professional liability
Insurance Programs
Insurance program, Company's risk per claim	0
General liability
Insurance Programs
Insurance program, Company's risk per claim	$ 0