Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000	2,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	250,000	250,000
Common stock, shares issued	133,265	132,247
Common stock, shares outstanding	131,525	130,350