INCOME TAXES - Movement of the valuation allowance (Details) - Allowance - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement of allowances
Beginning of the year	$ 71,469	$ 55,959	$ 52,985
Additions (Reversals)	(5,361)	14,486	(944)
Addition from acquisition of Recurrent			4,949
Foreign exchange effect	(709)	1,024	(1,031)
Closing balance	$ 65,399	$ 71,469	$ 55,959

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs which have been charged to costs and expenses net of the total of recoveries of amounts due the Entity that had previously been written off as uncollectible using allowances (the valuation accounts that are netted against the cost of an asset to value it at its carrying value) and total of reestablishments of reserves (liabilities established to represent expected future costs) that had previously been utilized.

No definition available.

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- Definition

Total of the foreign exchange effects in a given period to allowances or reserves.

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

+ References

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