Quarterly report pursuant to Section 13 or 15(d)

Business and Summary of Significant Accounting Principles (Narratives) (Details)

v3.7.0.1
Business and Summary of Significant Accounting Principles (Narratives) (Details)
$ in Thousands
 3 Months Ended
Mar. 31, 2017
USD ($)
payment
entity
Dec. 31, 2016
USD ($)
Business    
Year founded 1979  
Principles of Consolidation    
Number of VIEs | entity 5  
Recently Adopted Accounting Pronouncements    
Retained earnings (deficit) $ (36,557) $ 17,068
Accounts Receivable and Allowance for Doubtful Receivables    
Period past due for write-off of trade accounts receivable 120 days  
Number of installment plan payments | payment 12  
Maximum [Member]    
Accounts Receivable and Allowance for Doubtful Receivables    
Equipment installment plan payment term 24 months  
Accounting Standards Update 2016-09 [Member]    
Recently Adopted Accounting Pronouncements    
Retained earnings (deficit)   $ 7,100