Schedule II-Schedule of Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Provision for Inventories
Movement in schedule of valuation and qualifying accounts
Balance at beginning of period		$ 239,752	$ 258,435
Additions		530,000	120,000
Deductions		88,357	138,683
Balance at end of period	681,395	681,395	239,752
Provision for Accounts Receivables
Movement in schedule of valuation and qualifying accounts
Balance at beginning of period	1,698,506	2,186,190	2,078,944
Additions	27,300	50,000	107,246
Deductions		537,684
Balance at end of period	1,725,806	1,698,506	2,186,190
Deferred Tax Valuation
Movement in schedule of valuation and qualifying accounts
Balance at beginning of period	8,577,666	6,160,648	5,005,010
Additions	807,790	2,417,018	1,155,638
Balance at end of period	9,385,456	8,577,666	6,160,648
Provision for Rebates
Movement in schedule of valuation and qualifying accounts
Balance at beginning of period	26,793,666	21,993,267	16,158,795
Additions	19,115,643	17,912,447	19,615,388
Deductions	12,070,529	13,112,048	13,780,916
Balance at end of period	33,838,780	26,793,666	21,993,267
Accounts payable
Movement in schedule of valuation and qualifying accounts
Balance at end of period	$ 4,160,099	$ 3,611,962	$ 3,036,564

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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