Calculation of Net Income (Loss) and Number of Shares Used to Compute Basic and Diluted Earnings Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Net loss	$ (274,158)	$ (220,872)	$ (123,603)
Weighted average shares outstanding - basic and diluted	183,575	164,964	132,375
Net loss per share - basic and diluted	$ (1.49)	$ (1.34)	$ (0.93)