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Debt (Additional Information) (Details)
3 Months Ended 12 Months Ended
Feb. 17, 2017
USD ($)
Jun. 18, 2015
Mar. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
capital_lease_agreement
Mar. 31, 2017
USD ($)
Debt Instrument [Line Items]          
Outstanding line of credit issuance costs     $ 2,100,000    
Amortization expense     $ 100,000    
Debt instrument, leverage ratio, maximum     2.75    
Capital lease obligation       $ 700,000  
Amortization expense related to the capital lease     $ 100,000    
Capital lease accumulated depreciation     200,000    
Interest expense on capital lease     100,000    
Number of capital lease agreements | capital_lease_agreement       2  
Maximum          
Debt Instrument [Line Items]          
Dividends     $ 20,000,000    
Credit Agreement          
Debt Instrument [Line Items]          
Variable rate lower range basis spread   37.50%      
Variable rate higher range basis spread   75.00%      
Line of credit, base reference rate description   The base reference rate is the greater of the prime rate; federal funds effective rate (or the overnight bank funding rate, if greater) plus 50 basis points; or adjusted 1-month LIBOR plus 100 basis points.      
Amended Credit Facility | Federal Funds Effective Swap Rate          
Debt Instrument [Line Items]          
Variable rate lower range basis spread   0.50%      
Amended Credit Facility | LIBOR          
Debt Instrument [Line Items]          
Variable rate higher range basis spread   1.00%      
Third Amended Credit Agreement          
Debt Instrument [Line Items]          
Leverage ratio 3.25        
One-time leverage ratio maximum option 3.50        
ICR covenant limit 3.00        
Eurocurrency loans | Credit Agreement          
Debt Instrument [Line Items]          
Line of credit, LIBOR rate, minimum spread   137.50%      
Line of credit, LIBOR rate, maximum spread   175.00%      
Revolving Credit Facility | Third Amended Credit Agreement          
Debt Instrument [Line Items]          
Debt instrument, term 5 years        
Maximum borrowing capacity $ 450,000,000        
Additional borrowing capacity $ 175,000,000        
Outstanding borrowings       $ 131,000,000  
Revolving Credit Facility | Third Amended Credit Agreement | Minimum          
Debt Instrument [Line Items]          
Unused capacity, commitment fee percentage     20.00%    
Revolving Credit Facility | Third Amended Credit Agreement | Maximum          
Debt Instrument [Line Items]          
Unused capacity, commitment fee percentage     30.00%    
Interest rate swap | Revolving Credit Facility | Third Amended Credit Agreement          
Debt Instrument [Line Items]          
Hedged balance on debt instrument         $ 75,000,000
Germany          
Debt Instrument [Line Items]          
Capital lease, expiration date     44561    
Capital lease obligation     $ 5,700,000    
Amortization expense related to the capital lease     100,000    
Capital lease accumulated depreciation     $ 3,200,000 $ 3,300,000