Common Stock Equivalents Excluded From Diluted Net Income (Loss) Per Common Share (Detail) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents diluted net income (loss) per share inclusion anti-dilutive	5,775	5,534	7,447	7,813
RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents diluted net income (loss) per share inclusion anti-dilutive			906	1,214
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents diluted net income (loss) per share inclusion anti-dilutive	102	131	553	576
Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents diluted net income (loss) per share inclusion anti-dilutive			315	620
Shares of Common Stock Issuable Upon Conversion of Series B Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents diluted net income (loss) per share inclusion anti-dilutive	5,673	5,403	5,673	5,403