Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share Reconciliation [Abstract]
Weighted average number of common shares outstanding used in computing basic earnings per share	46,699	46,021
Net income (loss) attributable to common stockholders	$ 10,202	$ (1,926)
Earnings (loss) per share attributable to common stockholders	$ 0.22	$ (0.04)
Weighted Average Number of Shares Outstanding, Basic, Total	46,699	46,021
Add: Assumed exercise of stock options and stock awards	1,297	0
Diluted shares	47,996	46,021
Net income (loss) attributable to common stockholders	$ 10,202	$ (1,926)
Earnings (loss) per share attributable to common stockholders	$ 0.21	$ (0.04)
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. 1,212 potentially dilutive shares were excluded from the diluted earnings per shares calculation for the three months ended March 31, 2013.
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		1,212