CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
CONDENSED CONSOLIDATED BALANCE SHEETS
Common stock, par value (in dollars per share)	$ 0.005	$ 0.005
Common stock, shares authorized	240,000	240,000
Common stock, shares issued	203,895	203,759
Common stock, shares outstanding	165,655	165,776
Common stock in treasury, shares	38,240	37,983