Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets and Goodwill - Narrative (Details)

v3.10.0.1
Intangible Assets and Goodwill - Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]            
Amortization of intangible assets $ 2,382 $ 2,268 $ 4,790 $ 4,536    
Goodwill $ 101,511   $ 101,511   $ 99,811 $ 88,727
Customer relationships            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     3 years 11 months      
Trade names            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     9 years 1 month      
Minimum | Customer relationships            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     4 years      
Minimum | Trade names            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     10 years      
Maximum | Customer relationships            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     10 years      
Maximum | Trade names            
Finite-Lived Intangible Assets [Line Items]            
Finite-lived intangible asset, useful life (in years)     20 years