Commitments and Contingencies - Insurance and Regulatory Issues (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Insurance and Regulatory
Period for which insurance policies have been renewed	1 year
AFSC
Insurance and Regulatory
Percentage of total revenues attributable to subsidiary	3.00%
Specialty Pharmaceutical Management
Insurance and Regulatory
Per claim self-insured retention	$ 50
Aggregated self-insured retention	250
General liability
Insurance and Regulatory
Per claim un-aggregated self-insured retention	50
Professional liability
Insurance and Regulatory
Per claim un-aggregated self-insured retention	50
Managed care liability
Insurance and Regulatory
Per claim un-aggregated self-insured retention	1,000
Per class action claim un-aggregated self-insured retention	$ 10,000