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Income Taxes - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Schedule Of Income Taxes [Line Items] |  |  |
Statutory tax rate | 35.00% | 35.00% | 35.00%
Valuation allowance related to gross deferred tax assets | $ 3,114 | $ 2,670 |
Deferred tax assets operating loss carry forwards, total | 31,200 |  |
Unrecognized tax benefits, accrued interest | $ 100 | $ 100 | $ 100
Minimum |  |  |
Schedule Of Income Taxes [Line Items] |  |  |
Deferred tax assets operating loss carry forwards, expiration date | 2020 |  |
Maximum |  |  |
Schedule Of Income Taxes [Line Items] |  |  |
Deferred tax assets operating loss carry forwards, expiration date | 2036 |  |
PENNSYLVANIA |  |  |
Schedule Of Income Taxes [Line Items] |  |  |
Valuation allowance related to gross deferred tax assets | $ 3,100 |  |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68052875&loc=d3e28680-109314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319 + Details
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