Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Allowance for bad debts	$ 490,000	$ 586,000
Preferred stock - par value	$ 0.001	$ 0.001
Preferred stock - shares authorized	5,000,000	5,000,000
Preferred stock - shares issued	0	0
Common stock - par value	$ 0.001	$ 0.001
Common stock - shares authorized	75,000,000	75,000,000
Common stock - shares issued	34,737,801	34,156,561
Common stock - shares outstanding	30,320,216	29,738,976
Treasury stock - shares	4,417,585	4,417,585

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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