Annual report pursuant to Section 13 and 15(d)

Business and Summary of Significant Accounting Principles (Software Capitalization) (Details)

v3.8.0.1
Business and Summary of Significant Accounting Principles (Software Capitalization) (Details) - Internally Used Software
12 Months Ended
Dec. 31, 2017
Minimum  
Property, Plant and Equipment [Line Items]  
Useful life 3 years
Maximum  
Property, Plant and Equipment [Line Items]  
Useful life 5 years