Commitments and Contingencies - Additional Information (Detail) - USD ($)
 12 Months Ended
Mar. 08, 2016
Dec. 07, 2015
Jun. 17, 2015
Feb. 25, 2015
Feb. 15, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Jul. 31, 2015
Commitments and Contingencies [Line Items]                  
Total rent expense under operating leases           $ 6,200,000 $ 4,900,000 $ 4,700,000  
Line of credit facility, maximum borrowing capacity         $ 3,000,000.0        
Restricted cash         $ 5,000,000 $ 0 5,000,000    
Debt instrument, description of variable rate Basis         LIBOR plus 1%        
Debt instrument, basis spread on variable rate         1.00%        
Letters of credit outstanding, amount             $ 700,000    
Against Salem Hospital [Member]                  
Commitments and Contingencies [Line Items]                  
Loss Contingency, Damages Sought, Value     $ 9,300,000            
Loss Contingency, Counterclaim, Value                 $ 2,700,000
Settled Litigation | U.S. District Court for the Northern District of Illinois [Member]                  
Commitments and Contingencies [Line Items]                  
Litigation settlement, amount       $ 600,000          
Settled Litigation | Hughes Litigation Case [Member]                  
Commitments and Contingencies [Line Items]                  
Litigation settlement, amount   $ 3,900,000              
Line of Credit                  
Commitments and Contingencies [Line Items]                  
Debt instrument, term         3 years        
Office space | Minimum                  
Commitments and Contingencies [Line Items]                  
Lease term           1 year      
Office space | Maximum                  
Commitments and Contingencies [Line Items]                  
Lease term           11 years      
Other equipment | Minimum                  
Commitments and Contingencies [Line Items]                  
Lease term           1 year      
Other equipment | Maximum                  
Commitments and Contingencies [Line Items]                  
Lease term           3 years      
Subsequent Event | Settled Litigation | Hughes Litigation Case [Member]                  
Commitments and Contingencies [Line Items]                  
Litigation Settlement, Amount To Be Paid By Insurance $ 3,900,000