Employee Share-Based Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans	5
Shares Under Options, Granted	412,170	938,757
Estimated forfeiture rate	22.50%
Weighted average grant date fair value of options granted	$ 1.51	$ 1.53		$ 1.25
Intrinsic value of stock options exercised	$ 639,000	$ 103,000		$ 0
Common stock, par value	$ 0.01	$ 0.01
Stock-based compensation expense under share based plans	1,469,000	1,419,000		1,201,000
Total fair value of stock awards vested	55,000	24,000		72,000
Employee stock purchase plan, percentage of purchase price	85.00%
Unrecognized compensation expense	1,600,000
Expected weighted average recognition period for unrecognized compensation expense	1 year 29 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	$ 4.16
Common stock, par value	$ 0.01
Issuance of restricted stock awards, shares	126,000
Restricted share awards issued to employees	131,380		0	0
Purchase price of restricted share awards issued to employees	$ 0.01
Stock-based compensation expense under share based plans	$ 178,000		$ 18,000	$ 56,000
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
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	294,401
2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	1,200,000
Shares available for future grant	57,469
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	442,441
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	135,100	176,375		231,004
Weighted-average fair value of the shares issued under the ESPP Plans	$ 1.05	$ 0.78		$ 0.69
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