Long-term Debt - Narrative (Detail)
 3 Months Ended 12 Months Ended
Dec. 09, 2013
USD ($)
Feb. 15, 2013
USD ($)
Amendments
Dec. 06, 2012
USD ($)
Aug. 08, 2012
USD ($)
Mar. 31, 2016
USD ($)
Mar. 31, 2015
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Dec. 31, 2013
USD ($)
Dec. 31, 2012
USD ($)
Line of Credit Facility [Line Items]                    
Line of credit, maximum borrowing capacity       $ 390,000,000            
Percent of assets pledged for secured debt       100.00%            
Amortization of debt discount                 $ 900,000  
Deferred finance costs                 5,700,000  
Loss on extinguishment of debt             $ 0 $ 0 (15,918,000)  
Amortization of debt issuance costs         $ 30,000 $ 30,000 122,000 122,000 2,511,000  
Carrying value         386,107,000   $ 387,097,000 391,057,000    
Effective interest rate             3.75%      
Commitment fee percentage             0.50%      
Interest expense, debt             $ 15,100,000 15,900,000 22,900,000  
Interest costs capitalized               2,000,000 2,300,000  
Covenant terms, maximum indebtedness exclusions             $ 40,000,000      
Secured leverage ratio             3.75      
Term Facility                    
Line of Credit Facility [Line Items]                    
Line of credit, maximum borrowing capacity       $ 350,000,000            
Unamortized discount                   $ 7,000,000
Payments of special dividend       350,000,000            
Fair value             $ 385,200,000 $ 386,200,000    
Effective interest rate             3.87%      
Periodic principal payment             $ 1,000,000      
End of term payment             $ 373,200,000      
Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Line of credit, maximum borrowing capacity       40,000,000            
Effective interest rate               4.03%    
Interest rate, stated percentage               4.25%    
Letter of Credit                    
Line of Credit Facility [Line Items]                    
Line of credit, maximum borrowing capacity       10,000,000            
Swing Line Facility                    
Line of Credit Facility [Line Items]                    
Line of credit, maximum borrowing capacity       $ 5,000,000            
Federal Funds Effective Swap Rate | Term Facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             0.50%      
Federal Funds Effective Swap Rate | Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             0.50%      
London Interbank Offered Rate (LIBOR) | Term Facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             1.00%      
Interest rate, variable rate             2.75%      
London Interbank Offered Rate (LIBOR) | Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             1.00%      
Interest rate, variable rate             3.25%      
Base Rate | Term Facility                    
Line of Credit Facility [Line Items]                    
Interest rate, variable rate             1.75%      
Base Rate | Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Interest rate, stated percentage             2.25%      
First Amended Credit Facility                    
Line of Credit Facility [Line Items]                    
Payments of special dividend     $ 50,000,000              
First Amended Credit Facility | Term Facility                    
Line of Credit Facility [Line Items]                    
Additional borrowings     50,000,000              
Deferred finance costs     $ 1,200,000              
Second Amended Credit Facility | Term Facility                    
Line of Credit Facility [Line Items]                    
Deferred finance costs   $ 4,700,000                
Number of amendments | Amendments   2                
Line of credit, principal amount   $ 399,000,000                
Variable rate decrease   1.50%                
Basis spread on variable rate decrease in floor   0.22%                
Second Amended Credit Facility | Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Line of credit, principal amount                 0  
Variable rate decrease   1.50%                
Second Amended Credit Facility | Interest Expense | Term Facility                    
Line of Credit Facility [Line Items]                    
Debt instrument, fee amount                 $ 500,000  
Third Amended Credit Facility                    
Line of Credit Facility [Line Items]                    
Loss on extinguishment of debt $ 15,900,000                  
Amortization of debt issuance costs 9,200,000                  
Unamortized discount, net 5,700,000                  
Debt issuance cost 1,000,000                  
Third Amended Credit Facility | Term Facility                    
Line of Credit Facility [Line Items]                    
Line of credit, principal amount $ 396,000,000                  
Basis spread on variable rate decrease in floor (75.00%)                  
Amended Facility                    
Line of Credit Facility [Line Items]                    
Carrying value         386,100,000   $ 387,100,000 $ 391,100,000    
Unrestricted cash and cash equivalents limit for the secured leverage ratio         $ 40,000,000          
Secured leverage ratio         3.75          
Amended Facility | Revolving credit facility                    
Line of Credit Facility [Line Items]                    
Line of credit, principal amount         $ 0   0      
Amended Facility | Term loan                    
Line of Credit Facility [Line Items]                    
Carrying value         386,100,000   387,100,000      
Fair value         $ 386,100,000   $ 385,200,000      
Effective interest rate         3.86%   3.87%      
Periodic principal payment         $ 1,000,000          
End of term payment         $ 373,200,000          
Minimum | London Interbank Offered Rate (LIBOR) | Term Facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             1.00%      
Minimum | Base Rate | Term Facility                    
Line of Credit Facility [Line Items]                    
Basis spread on variable rate             2.00%