Earnings Per Share Reconciliation of Shares Used in Calculating Earnings Per Basic and Diluted Shares (Details) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Weighted average common shares outstanding—basic	25,879	25,535	25,811	24,323
Dilutive effect of stock-based awards	410	843	684	940
Dilutive effect of convertible senior notes	1,043	805	1,118	298
Dilutive effect of warrants	0	0	9	0
Weighted average common shares outstanding—diluted	27,332	27,183	27,622	25,561