Employee Share-Based Compensation Plans - Additional Information (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) CompensationPlan $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans | CompensationPlan	5
Shares under options, Granted	304,000	352,500
Estimated forfeiture rate	22.50%
Weighted average grant date fair value of options granted | $ / shares	$ 2.50	$ 2.53	$ 1.51
Intrinsic value of stock options exercised | $	$ 1,000	$ 1,200	$ 639
Common stock, par value | $ / shares	$ 0.01	$ 0.01
Stock-based compensation expense under share based plans | $	$ 1,593	$ 1,512	1,469
Total fair value of stock awards vested | $	$ 422	$ 797	$ 55
Employee stock purchase plan, percentage of purchase price	85.00%
Unrecognized compensation expense | $	$ 1,700
Expected weighted average recognition period for unrecognized compensation expense	1 year 2 months 12 days
Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for shares of restricted stock vested	4 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for shares of restricted stock vested	5 years
Weighted average grant date fair value of options granted | $ / shares	$ 7.00	$ 7.01
Common stock, par value | $ / shares	$ 0.01
Issuance of restricted stock awards, shares	168,000
Restricted share awards issued to employees	91,000	84,800	131,380
Purchase price of restricted share awards issued to employees | $ / shares	$ 0.01	$ 0.01
Stock-based compensation expense under share based plans | $	$ 557	$ 386	$ 178
Minimum [Member] | Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for shares of restricted stock vested	3 years
Maximum [Member] | Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for shares of restricted stock vested	5 years
1996 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding shares of common stock	15.00%
Stock option grants	650,000
Shares available for future grant	0
Stock option plan, expiration date	Jun. 30, 2006
Stock option grants	650,000
Shares available for future grant	0
2000 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	4,000,000
Shares available for future grant	100,175
Stock option grants	4,000,000
Shares available for future grant	100,175
2003 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	500,000
Shares available for future grant	0
Stock option plan, expiration date	May 22, 2013
Stock option grants	500,000
Shares available for future grant	0
2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	1,700,000
Shares available for future grant	21,702
Stock option grants	1,700,000
Shares available for future grant	21,702
Share issued	1,500,000
Stock option plan, effective date	Jun. 11, 2008
2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	1,100,000
Shares available for future grant	28,197
Stock option grants	1,100,000
Shares available for future grant	28,197
Stock option plan, effective date	Jun. 06, 2012
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share issued	114,431	103,401	135,100
Weighted-average fair value of the shares issued under the ESPP Plans | $ / shares	$ 1.54	$ 1.75	$ 1.05