Quarterly report pursuant to Section 13 or 15(d)

Property, Equipment and Software - Additional Information (Details)

v3.8.0.1
Property, Equipment and Software - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Property, Plant and Equipment [Line Items]          
Depreciation and amortization expense for property, equipment and software $ 6.9 $ 6.2 $ 20.4 $ 18.2  
Carrying amount of capitalized software development costs 68.8   68.8   $ 55.4
Accumulated depreciation of capitalized software development costs (25.4)   (25.4)   $ (19.8)
Software          
Property, Plant and Equipment [Line Items]          
Depreciation and amortization expense for property, equipment and software $ 2.2 $ 1.6 $ 5.7 $ 4.2