|
Stockholders' Equity - Additional Information (Detail) (USD $)
|
3 Months Ended |
12 Months Ended |
|
Jun. 30, 2010
|
Dec. 31, 2014
Plans
|
Dec. 31, 2013
|
Dec. 31, 2012
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Preferred stock, shares authorized |
|
10,000,000 |
10,000,000 |
|
| Preferred stock, shares outstanding |
|
0 |
0 |
|
| Common stock, shares authorized |
|
40,000,000 |
40,000,000 |
|
| Common stock, shares outstanding |
|
14,358,000 |
14,184,000 |
|
| Number of equity incentive plans |
|
1 |
|
|
| Shares outstanding under equity incentive plans |
|
980,000 |
893,000 |
|
| Common stock authorized for issuance there-under |
|
1,000,000 |
|
|
| Common stock authorized for issuance additional |
|
348,208 |
|
|
| Term of vesting schedule |
|
10 years |
|
|
| Vested share exercised |
|
3 months |
|
|
| Vesting of outstanding options |
|
100.00% |
|
|
| Period of option granted vest |
|
3 years |
|
|
| Fair value assumption, risk-free interest rates |
|
1.56% |
1.81% |
0.91% |
| Fair value assumption, expected dividend yields |
|
0.00% |
0.00% |
0.00% |
| Aggregate intrinsic value closing stock price |
|
$ 1.09 |
|
|
| Equity ownership percentage to benefit China employees |
38.00% |
|
|
|
| Price of warrant |
1.00 |
|
|
|
| Vesting period of warrant |
|
Vesting to occur one-third upon the first anniversary of the warrant and the remaining two-thirds to vest on a monthly basis over the succeeding 24 months. |
|
|
| Investment warrants expiration period (years) |
6 years |
|
|
|
| Warrant exercise date |
|
May 05, 2013 |
|
|
| Fair value of options granted |
|
$ 0.93 |
$ 0.58 |
$ 0.54 |
| Unrecognized compensation expense related to non-vested stock options |
|
$ 277,000 |
|
|
| Recognition of unrecognized compensation expense, weighted-average period (in years) |
|
1 year 8 months 12 days |
|
|
| Fair value of options that vested |
|
80,000 |
68,000 |
110,000 |
| Stock issued during period, stock options exercised |
|
174,000 |
|
|
| Cash received from exercise of stock options |
|
137,000 |
|
|
| Stock options exercise price |
|
$ 0.79 |
|
|
| Minimum [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Fair value assumption, expected volatility |
|
93.00% |
93.00% |
93.00% |
| Fair value assumption, expected term (years) |
|
3 years |
3 years |
3 years |
| Maximum [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Fair value assumption, expected volatility |
|
109.00% |
109.00% |
109.00% |
| Fair value assumption, expected term (years) |
|
7 years |
7 years |
7 years |
| 2006 Equity Incentive Plan [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Shares outstanding under equity incentive plans |
|
980,000 |
|
|
| Shares available for grant under equity incentive plans |
|
206,000 |
|
|
| Hong Kong Subsidiary [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Value funded to affiliates |
1,000,000 |
|
|
|
| Agreed additional funding to affiliates |
1,000,000 |
|
|
|
| Estimated fair value of warrants |
|
365,000 |
|
|
| Warrant performance period (years) |
|
3 years |
|
|
| Stock expenses on equity-based payments related to warrant |
|
$ 0 |
$ 40,000 |
$ 122,000 |