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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Operating Loss Carryforwards [Line Items] |  |  |
Excess tax benefit obtained by company | $ 1.3 | $ 1.0 | $ 1.0
Company's federal net operating losses for tax return purposes | 12.3 |  |
State and foreign tax credit carry forwards, expiration year | 2022 |  |
Likelihood percentage of being realized upon ultimate settlement with the relevant tax authority | 50.00% |  |
Unrecognized tax benefits | 0 | 0 |
Changes in unrecognized benefits | 0 | 0 | 0
State and Local Jurisdiction [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
State and foreign tax credit carry forwards, expiration description | Begin to expire in 2022 |  |
State and foreign tax credit carry forwards | $ 2.6 |  |

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- Definition Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11283-113907 + Details
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Carryforwards -URI http://asc.fasb.org/extlink&oid=6506874 + Details
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