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Benefit Plan (Details) (USD $) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 31, 2012 | Jan. 31, 2012 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Benefit Plan (Textual) [Abstract] |  |  |  |  |
Matching contribution to benefits plan | 4.00% | 3.00% | 100.00% | 2.00% |
Employee matching contribution |  |  | 50.00% |  |
Contribution compensation maximum |  |  | 5.00% |  |
Expenses on contribution charged |  |  | $ 391,000 | $ 160,000 | $ 0
Interest expense related to Board of Directors deferred compensation plan |  |  | 13,000 | 17,000 | 19,000
Interest expense related to officer non-qualified deferred compensation program |  |  | $ 32,000 | $ 36,000 | $ 40,000
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 |  |  | 2,400 | 4,726 |
Number of shares available under employee stock purchase plan |  |  | 5,040 |  |

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- Definition Defined contribution plan first compensation slab having employer matching contribution. + References No definition available. + Details
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- Definition The compensation expense recognized during the period pertaining to the deferred compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 6, 7 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64, 65 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
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