Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Narrative) (Details)

v3.10.0.1
Fair Value Measurements (Narrative) (Details) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
May 25, 2018
Dec. 15, 2014
Fair Value Measurements          
Fair value asset transfers between Levels 1, 2 and 3 $ 0.00        
Face amount         $ 172,500,000
Revolving credit facility 0 $ 81,168,000      
Convertible Notes          
Fair Value Measurements          
Face amount 172,500,000 172,500,000      
Convertible Notes 0 158,990,000      
Convertible Notes Due 2023          
Fair Value Measurements          
Face amount 345,000,000 0   $ 345,000,000  
Convertible Notes 294,725,000 0      
Credit Agreement          
Fair Value Measurements          
Revolving credit facility 0 81,168,000      
Carrying Value | Convertible Notes          
Fair Value Measurements          
Convertible Notes 165,711,000 158,990,000      
Carrying Value | 2023 Convertible Notes          
Fair Value Measurements          
Convertible Notes 294,725,000        
Total liabilities 339,024,000        
Fair Value | Convertible Notes          
Fair Value Measurements          
Convertible Notes 174,101,000 180,180,000      
Recurring Basis          
Fair Value Measurements          
Fair value, measurement with unobservable inputs, asset value 6,346,000 5,185,000      
Recurring Basis | Fair Value          
Fair Value Measurements          
Total liabilities 6,928,000 7,145,000      
Recurring Basis | Other non-current assets          
Fair Value Measurements          
Fair value, measurement with unobservable inputs, asset value 6,346,000        
FinaConnect, Inc.          
Fair Value Measurements          
Contingent Consideration first year 0 $ 2,286,000 $ 1,929,000    
Wheelhouse Analytics, LLC          
Fair Value Measurements          
Contingent Consideration first year $ 2,193,000