Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Allowance for bad debts	$ 690	$ 760
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	32,486,851	31,966,432
Common stock - shares outstanding	28,069,266	27,548,847
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.

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