Income Per Share - Weighted Average Number of Common Shares Outstanding (Detail) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Weighted average shares outstanding - basic	51,283	50,975	51,226	50,805
Effect of dilutive stock-based compensation	347	442	361	495
Effect of convertible notes		6,307		5,946
Effect of common stock warrants		3,435		3,156
Weighted average shares outstanding - diluted	51,630	61,159	51,587	60,402