Quarterly report pursuant to Section 13 or 15(d)

Segment Reporting (Narrative) (Details)

v3.8.0.1
Segment Reporting (Narrative) (Details)
3 Months Ended
Mar. 31, 2018
USD ($)
segment
Mar. 31, 2017
USD ($)
Dec. 31, 2017
USD ($)
Segment Reporting Information [Line Items]      
Number of business segments | segment 2    
Revenue $ 138,967,000 $ 149,887,000  
Foreign Locations [Member]      
Segment Reporting Information [Line Items]      
Revenue 0 $ 0  
Long lived assets $ 0   $ 0