Net Income (Loss) Per Share - Potentially Dilutive Securities Not Included in Computation of Diluted Net Loss Per Share (Detail) - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
DSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in the computation of diluted net loss per share (in shares)	28	90
Weighted Average Price per Share, anti-dilutive securities excluded from computation of earnings per share (in dollars per share)	$ 0.00	$ 0.00
SARs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in the computation of diluted net loss per share (in shares)	307	480
Weighted Average Price per Share, anti-dilutive securities excluded from computation of earnings per share (in dollars per share)	$ 11.28	$ 10.64
Restricted stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in the computation of diluted net loss per share (in shares)	2,137	2,669
Weighted Average Price per Share, anti-dilutive securities excluded from computation of earnings per share (in dollars per share)	$ 0.00	$ 0.00