|**Derivatives and Financial Instruments (Gain/(Loss), Net of Tax Recognized in Income) (Details) (USD $)In Thousands, unless otherwise specified**                                                                                                                        | 12 Months Ended                                                                                                         
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------
|
|Designated as hedges [Member] | Interest rate swap contracts [Member] | FHLB advance [Member] | Other income [Member]                                                                                                                                                     |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | $ 0                                                                                                                     
|Not designated as hedges [Member] | Continuing operations [Member]                                                                                                                                                                                                        |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | 204                                                                                                                     
|Not designated as hedges [Member] | Continuing operations [Member] | Mortgage loan rate lock commitments [Member]                                                                                                                                                         |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | 152                                                                                                                     
|Not designated as hedges [Member] | Continuing operations [Member] | Mortgage loan forward sales and MBS [Member]                                                                                                                                                         |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | 52                                                                                                                      
|Not designated as hedges [Member] | Discontinued operations [Member]                                                                                                                                                                                                      |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | 0                                                                                                                       
|Not designated as hedges [Member] | Discontinued operations [Member] | Mortgage loan rate lock commitments [Member]                                                                                                                                                       |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | 0                                                                                                                       
|Not designated as hedges [Member] | Discontinued operations [Member] | Mortgage loan forward sales and MBS [Member]                                                                                                                                                       |                                                                                                                         
|**Derivative Instruments, Gain (Loss) [Line Items]**                                                                                                                                                                                                                      |                                                                                                                         
|Gain (loss), net of tax recognized in income                                                                                                                                                                                                                              | $ 0                                                                                                                     
|                                                                                                                                                                                                                                                                         
|[1]
              For 2011 and 2010, recognized in "Net loss from discontinued operations" in FNB's Consolidated Statements of Operations.[2]
              Recognized in “Net loss from discontinued operations” in the Company’s Consolidated Statements of Operations. | [1]                                                                                                                     
|[1]                                                                                                                                                                                                                                                                       | For 2011 and 2010, recognized in "Net loss from discontinued operations" in FNB's Consolidated Statements of Operations.
|[2]                                                                                                                                                                                                                                                                       | Recognized in “Net loss from discontinued operations” in the Company’s Consolidated Statements of Operations.           

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