Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share Reconciliation [Abstract]
Weighted average number of common shares outstanding used in computing basic earnings per share	46,021	45,460
Net income attributable to common stockholders	$ (1,926)	$ 4,871
Earnings per share attributable to common stockholders - basic	$ (0.04)	$ 0.11
Weighted Average Number of Shares Outstanding, Basic, Total	46,021	45,460
Add: Assumed exercise of stock options and stock awards	0	1,475
Diluted shares	46,021	46,935
Net income attributable to common stockholders	$ (1,926)	$ 4,871
Earnings per share attributable to common stockholders - diluted	$ (0.04)	$ 0.10
Earnings Per Share Reconciliation Disclosure	Basic earnings per share is calculated by dividing net earnings by the weighted-average number of shares of Common Stock outstanding during the period. Diluted earnings per share is calculated similarly but includes potential dilution from the exercise of stock options and stock awards, except when the effect would be anti-dilutive.