Income Per Share - Weighted Average Number of Common Shares Outstanding (Detail) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]
Weighted average shares outstanding - basic	50,814	51,244	50,719	51,832
Effect of dilutive stock-based compensation	464	504	519	533
Effect of convertible notes	6,033	7,464	5,798	7,682
Effect of common stock warrants	3,224	5,678	3,042	5,940
Weighted average shares outstanding - diluted	60,535	64,890	60,078	65,987