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Benefit Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified | 1 Months Ended | 12 Months Ended | 1 Months Ended
--- | --- | --- | ---
Oct. 31, 2012 | Jan. 31, 2012 | May 31, 2011 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Jan. 31, 2014 Subsequent Event [Member]
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Percentage of matching contribution to benefits plan | 4.00% | 3.00% | 2.00% |  |  |  | 4.25%
Expenses on contribution charged |  |  |  | $ 0.5 | $ 0.4 | $ 0.2 |
Number of shares of common stock issuable under employee stock purchase plan of 2002 |  |  |  | 55,000 |  |  |
Number of shares issued under employee stock purchase plan |  |  |  | 1,098 | 2,400 | 4,726 |
Number of shares available under employee stock purchase plan |  |  |  | 3,942 |  |  |

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- Definition Number of shares of common stock issuable under employee stock purchase plan of two thousand two. + References No definition available. + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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