Annual report pursuant to Section 13 and 15(d)

Nature of Business and Significant Accounting Policies - Narrative (Details)

v3.8.0.1
Nature of Business and Significant Accounting Policies - Narrative (Details)
 1 Months Ended 12 Months Ended
May 31, 2016
Dec. 31, 2017
USD ($)
TradeName
contract
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Property, Plant and Equipment [Line Items]        
Stock split, conversion ratio 2      
Percentage of contracts with the government   82.00% 80.00% 77.00%
Number of contract types | contract   3    
Deferred compensation plan expense   $ 1,900,000 $ 1,700,000 $ 1,900,000
Impairment of intangible assets   $ 0 0 $ 0
Acquired intangible assets, weighted average useful life   12 years 2 months 12 days    
Retained earnings   $ 267,902,000 $ 231,733,000  
Servicing Contracts        
Property, Plant and Equipment [Line Items]        
Acquired intangible assets, weighted average useful life   12 years 7 months 6 days    
Servicing Contracts | Minimum        
Property, Plant and Equipment [Line Items]        
Finite-lived intangible assets, useful life   7 years    
Servicing Contracts | Maximum        
Property, Plant and Equipment [Line Items]        
Finite-lived intangible assets, useful life   16 years    
Trade names        
Property, Plant and Equipment [Line Items]        
Finite-lived intangible assets, useful life   9 years    
Number of trade names | TradeName   4    
Acquired technologies        
Property, Plant and Equipment [Line Items]        
Finite-lived intangible assets, useful life   11 years    
Other Capitalized Property Plant and Equipment | Minimum        
Property, Plant and Equipment [Line Items]        
Property, plant and equipment, useful life   3 years    
Other Capitalized Property Plant and Equipment | Maximum        
Property, Plant and Equipment [Line Items]        
Property, plant and equipment, useful life   15 years    
Land, Buildings and Improvements | Minimum        
Property, Plant and Equipment [Line Items]        
Property, plant and equipment, useful life   15 years    
Land, Buildings and Improvements | Maximum        
Property, Plant and Equipment [Line Items]        
Property, plant and equipment, useful life   20 years    
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09        
Property, Plant and Equipment [Line Items]        
Retained earnings   $ 1,500,000