Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Allowance for sales credit memos	$ 1,184	$ 963
Preferred stock, shares authorized	1,000	1,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, shares authorized	100,000	100,000
Common stock, shares issued	37,957	37,945
Common stock, shares outstanding	37,957	37,945