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Employee Benefit Plan - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Compensation And Retirement Disclosure [Abstract] |  |  |
Matches employee compensation for participating employees | 2.00% |  |
Fully vested in employer contributions | 5 years |  |
Defined contribution this plan | $ 343,000 | $ 322,000 | $ 316,000

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- Definition Defined contribution plan vesting period. + References No definition available. + Details
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- Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration

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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 Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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