SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	$ 3,800	$ 3,900	$ 3,043
Accruals	15,581	12,871	10,746
Payments (Credits)	(16,368)	(12,971)	(9,889)
End of Period	3,013	3,800	3,900
Accrued returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	1,346	1,733	1,559
Accruals	716	694	339
Payments (Credits)	(1,241)	(1,081)	(165)
End of Period	821	1,346	1,733
Reserves for prompt pay discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	595	625	575
Accruals	5,806	5,448	4,905
Payments (Credits)	(5,744)	(5,478)	(4,855)
End of Period	657	595	625
Accrued wholesaler service fees
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	735	745	588
Accruals	4,403	4,118	3,482
Payments (Credits)	(4,299)	(4,128)	(3,325)
End of Period	839	735	745
Accrued rebates and chargebacks
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	1,124	797	321
Accruals	4,656	2,611	2,020
Payments (Credits)	(5,084)	(2,284)	(1,544)
End of Period	$ 696	$ 1,124	$ 797

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

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- Definition

Amount of increase (decrease) in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from adjustments.

+ 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

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.

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+ References

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