XML 21 R9.htm IDEA: XBRL DOCUMENT v3.8.0.1
RECEIVABLES
9 Months Ended
Sep. 30, 2017
Receivables [Abstract]  
RECEIVABLES
RECEIVABLES
A summary of accounts receivable as of September 30, 2017 and December 31, 2016 is as follows (in thousands):
 
 
September 30, 2017
 
December 31, 2016
 
(unaudited)
 
 
Trade accounts receivable
$
194,722

 
$
230,889

Unbilled revenues
99,943

 
39,719

Allowance for doubtful accounts
(12,709
)
 
(7,835
)
Total
$
281,956

 
$
262,773