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Income Taxes - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Income Tax Contingency [Line Items] |  |  |
U.S. federal tax statutory rate | 35.00% | 35.00% | 35.00%
Net operating loss | $ 14,700,000 |  |
Current income tax | 475,000 | 7,000 | 0
Deferred tax asset related to net operating loss carryforwards | 17,215,000 | 13,926,000 |
Unrealized excess tax benefits from stock-based compensation | 1,800,000 |  |
Unrecognized tax benefits | 0 |  |
Net current deferred tax asset (liability) | 6,335,000 | (4,600,000) |
Domestic Tax Authority [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Net operating loss | 50,900,000 |  |
Stock-based compensation related to unrealized excess tax benefits | 4,800,000 |  |
State and Local Jurisdiction [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Net operating loss | 34,000,000 |  |
Stock-based compensation related to unrealized excess tax benefits | $ 3,500,000 |  |

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