| **Restriction on Cash and Due From Banks** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
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| **Cash and Cash Equivalents [Abstract]**   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Restriction on Cash and Due From Banks     | RESTRICTION ON CASH AND DUE FROM BANKSThe Corporation considers all liquid investments with original maturities of three months or less to be cash equivalents. As of December 31, 2012, cash and cash equivalents is defined to include cash on hand, deposits in other institutions and federal funds sold.Effective October 3, 2008, the FDIC’s insurance limits temporarily increased to $250,000. On July 21, 2010, the Dodd-Frank Wall Street Reform and Consumer Protection Act (“Dodd-Frank Act”) was signed into law, which, in part, permanently raised the standard maximum deposit insurance amount to $250,000.  At December 31, 2012, the Corporation’s interest-bearing cash accounts held at other institutions exceeded federally insured limits by approximately $33,228,000. Each correspondent bank’s financial performance and market rating are reviewed on a quarterly basis to ensure the Corporation has deposits only at institutions providing minimal risk for those exceeding the federally insured limits.On November 9, 2010, the FDIC implemented section 343 of the Dodd-Frank Act providing unlimited insurance coverage on noninterest-bearing transaction accounts.  Beginning December 31, 2010, through December 31, 2012, all noninterest-bearing transaction accounts are fully insured, regardless of the balance of the account, at all FDIC-insured institutions.  The Corporation’s noninterest-bearing transaction deposits at other institutions of approximately $6,909,000 were fully insured at December 31, 2012.  As of January 1, 2013, noninterest-bearing transaction deposit accounts are no longer insured separately from other accounts at the same FDIC-insured institution.  Instead, noninterest-bearing transaction accounts will be added to any of the Corporations's other accounts, and the aggregate balance insured up to at least the Standard Maximum Deposit Insurance Amount of $250,000, at each institution.Additionally, the Corporation had approximately $3,508,000 at the Federal Home Loan Bank and Federal Reserve Bank, which are government-sponsored entities not insured by the FDIC.The Corporation is required to maintain reserve funds in cash and/or on deposit with the Federal Reserve Bank.  The reserve required at December 31, 2012, was $24,181,000. |

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| - Definition
The entire disclosure for cash and cash equivalent footnotes,  which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section H -Subsection 3Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4273-108586Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9, 10 -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 6.H.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13728-122682Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 -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.
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