Earnings Per Share - Calculation of Basic and Diluted Weighted Average Shares Outstanding and Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Basic:
Net loss	$ (188,784)	$ (327,388)
Net income attributable to participating securities	0	0
Net loss attributable to common stock - basic	(188,784)	(327,388)
Diluted:
Net loss	(188,784)	(327,388)
Net income attributable to participating securities	0	0
Net loss attributable to common stock - diluted	$ (188,784)	$ (327,388)
Weighted average shares (denominator):
Weighted average shares - basic (in shares)	55,713	55,181
Dilutive effect of stock options (in shares)	0	0
Dilutive effect of convertible notes (in shares)	0	0
Weighted average shares - diluted (in shares)	55,713	55,181
Basic loss per share (usd per share)	$ (3.39)	$ (5.93)
Diluted loss per share (usd per share)	$ (3.39)	$ (5.93)