Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended	12 Months Ended
	May 10, 2016	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 07, 2018	Jun. 30, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Percentage of purchase of shares under tender offer as to common stock issued and outstanding	24.80%
Common stock repurchase, amount			$ 7,089,000	$ 8,085,000	$ 7,988,000
Repurchase of stock cost of repurchase of stock					$ 200
Tender Offers [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Repurchase of shares	8,000,000
Purchase price per share of common stock	$ 7.75
Common stock repurchased, shares	5,237,843
Treasury stock acquired, average purchase price per share	$ 7.75
Total cost of shares repurchased	$ 40,600,000
Common stock repurchase, amount	40,800,000
Repurchase of stock cost of repurchase of stock	$ 200,000
Period of expiration of tender offer			Jun. 08, 2016
Tender Offers [Member] | Jay Hoag [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Percentage of voting securities	5.00%
Tender Offers [Member] | TCV [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchased, shares	3,379,249
Tender Offers [Member] | Rogram LLC [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchased, shares	308,713
November 2018 Stock Repurchase Plan [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchased, shares		243,425
Treasury stock acquired, average purchase price per share		$ 12.82
Common stock repurchase, amount		$ 3,100,000
Common stock repurchase authorized amount						$ 25,000,000
June 2016 Repurchase Program [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchased, shares			211,729	749,437	980,329
Common stock repurchase, amount			$ 3,900,000	$ 8,100,000	$ 8,000,000
Common stock repurchase authorized amount							$ 20,000,000
Stock repurchase program expiration date			Jun. 30, 2017
2007 and 2017 Plans [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock reserved		3,334,912	3,334,912