Income Per Share - Weighted Average Number of Common Shares Outstanding (Detail) 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 shares outstanding - basic	50,975	50,524	50,805	51,392
Effect of dilutive stock-based compensation	442	460	495	503
Effect of convertible notes	6,307	5,416	5,946	6,187
Effect of common stock warrants	3,435	3,702	3,156	4,631
Weighted average shares outstanding - diluted	61,159	60,102	60,402	62,713