v2.4.0.8

Summary of Information About Stock Options Outstanding (Detail) (USD $) In Thousands, except Share data, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011
Schedule Of Stock Option Activity [Line Items] |  |
Options outstanding, Number of Options | 2,313,526 | 3,614,530
Options outstanding, Weighted average remaining life (years) | 7 years 10 months 13 days | 6 years 8 months 1 day
Options outstanding, Aggregate intrinsic value | $ 2,845 | $ 6,889
Options exercisable, Number of Options | 808,633 | 1,008,031
Options exercisable, Weighted average remaining life (years) | 6 years 5 months 5 days | 5 years 10 months 28 days
Options exerciseable, Aggregate intrinsic value | 2,471 | 5,082
$0.38 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 0.38 | $ 0.38
Options outstanding, Number of Options | 57,264 | 145,406
Options outstanding, Weighted average remaining life (years) | 8 years 26 days | 9 years 26 days
Options outstanding, Aggregate intrinsic value | 385 | 978
Options exercisable, Number of Options | 57,264 | 145,406
Options exercisable, Weighted average remaining life (years) | 8 years 26 days | 9 years 26 days
Options exerciseable, Aggregate intrinsic value | 385 | 978
$1.34 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 1.34 | $ 1.34
Options outstanding, Number of Options | 106,777 | 257,680
Options outstanding, Weighted average remaining life (years) | 3 years 1 month 6 days | 4 years 1 month 6 days
Options outstanding, Aggregate intrinsic value | 617 | 1,489
Options exercisable, Number of Options | 106,777 | 257,680
Options exercisable, Weighted average remaining life (years) | 3 years 1 month 6 days | 4 years 1 month 6 days
Options exerciseable, Aggregate intrinsic value | 617 | 1,489
$1.92 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 1.92 | $ 1.92
Options outstanding, Number of Options | 23,143 | 23,143
Options outstanding, Weighted average remaining life (years) | 4 years 3 months | 5 years 3 months 4 days
Options outstanding, Aggregate intrinsic value | 120 | 120
Options exercisable, Number of Options | 23,143 | 23,143
Options exercisable, Weighted average remaining life (years) | 4 years 3 months | 5 years 3 months 4 days
Options exerciseable, Aggregate intrinsic value | 120 | 120
$2.74 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 2.74 | $ 2.74
Options outstanding, Number of Options | 186,286 | 312,572
Options outstanding, Weighted average remaining life (years) | 4 years 7 months 13 days | 5 years 6 months 15 days
Options outstanding, Aggregate intrinsic value | 815 | 1,368
Options exercisable, Number of Options | 186,286 | 307,572
Options exercisable, Weighted average remaining life (years) | 4 years 7 months 13 days | 5 years 6 months 15 days
Options exerciseable, Aggregate intrinsic value | 815 | 1,346
$3.29 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 3.29 | $ 3.29
Options outstanding, Number of Options | 183,442 | 564,286
Options outstanding, Weighted average remaining life (years) | 6 years 9 months 7 days | 7 years 6 months
Options outstanding, Aggregate intrinsic value | 703 | 2,163
Options exercisable, Number of Options | 126,014 | 212,929
Options exercisable, Weighted average remaining life (years) | 6 years 8 months 19 days | 7 years 4 months 6 days
Options exerciseable, Aggregate intrinsic value | 483 | 816
$5.91 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 5.91 | $ 5.91
Options outstanding, Number of Options | 169,857 | 363,142
Options outstanding, Weighted average remaining life (years) | 7 years 7 months 21 days | 8 years 4 months 28 days
Options outstanding, Aggregate intrinsic value | 205 | 438
Options exercisable, Number of Options | 42,571 |
Options exercisable, Weighted average remaining life (years) | 7 years 7 months 2 days |
Options exerciseable, Aggregate intrinsic value | 51 |
$7.12 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price | $ 7.12 | $ 7.12
Options outstanding, Number of Options | 1,586,757 | 1,887,000
Options outstanding, Weighted average remaining life (years) | 8 years 9 months 7 days | 6 years 6 months 29 days
Options outstanding, Aggregate intrinsic value |  |
Options exercisable, Number of Options | 266,578 |
Options exercisable, Weighted average remaining life (years) | 8 years 6 months 11 days |
Options exerciseable, Aggregate intrinsic value |  |
$1.68 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price |  | $ 1.68
Options outstanding, Number of Options |  | 58,286
Options outstanding, Weighted average remaining life (years) |  | 2 years 10 months 2 days
Options outstanding, Aggregate intrinsic value |  | 317
Options exercisable, Number of Options |  | 58,286
Options exercisable, Weighted average remaining life (years) |  | 2 years 10 months 2 days
Options exerciseable, Aggregate intrinsic value |  | 317
$1.96 |  |
Schedule Of Stock Option Activity [Line Items] |  |
Exercise price |  | $ 1.96
Options outstanding, Number of Options |  | 3,015
Options outstanding, Weighted average remaining life (years) |  | 9 years 26 days
Options outstanding, Aggregate intrinsic value |  | 16
Options exercisable, Number of Options |  | 3,015
Options exercisable, Weighted average remaining life (years) |  | 9 years 26 days
Options exerciseable, Aggregate intrinsic value |  | $ 16

X
- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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