Quarterly report pursuant to Section 13 or 15(d)

Business and Summary of Significant Accounting Principles (Surcharges Reported Gross) (Details)

v3.7.0.1
Business and Summary of Significant Accounting Principles (Surcharges Reported Gross) (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Surcharges reported gross $ 818 $ 991 $ 1,650 $ 2,022