Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000	150,000
Common stock, shares issued	77,048	76,549
Treasury stock, shares	25,920	9,941