| **Commitments and Contingencies**            | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Commitments and Contingencies [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Commitments and Contingencies                | Commitments and ContingenciesIn the ordinary course of operations, FNB and its subsidiaries are party to various legal proceedings. On March 6, 2012, Howe Barnes Hoefer & Arnett, Inc., an affiliate of Raymond James Financial, Inc., filed a complaint in Wake County Superior Court in North Carolina seeking monetary damages against FNB and CommunityOne. The complaint alleged, among other things, breach of an agreement among FNB, CommunityOne, Howe Barnes and Sandler O'Neill & Partners, L.P., reformation of such agreement due to mutual mistake, and breach of a financial advisory agreement between FNB and Howe Barnes. The parties agreed to a settlement of the matter on December 7, 2012 and the legal proceedings have been stayed pending final execution of the settlement documents and receipt of regulatory non-objection.  The settlement had no material financial impact to FNB. In addition, from time to time, we are subject to various claims, lawsuits, disputes with third parties, investigations and pending actions involving various allegations against us incident to the operation of our business. FNB and its subsidiaries are not involved in, nor have they terminated during 2012, any pending legal proceedings other than routine, nonmaterial proceedings occurring in the ordinary course of business.FNB leases certain facilities and equipment for use in its business. The lease for facilities generally runs for periods of 5 to 10 years with various renewal options, while leases for equipment generally have terms not in excess of 5 years. The majority of the leases for facilities contain rental escalation clauses tied to changes in price indices. Certain real property leases contain purchase options. Management expects that most leases will be renewed or replaced with new leases in the normal course of business.Future obligations at December 31, 2012 for minimum rentals under non-cancelable operating lease commitments, primarily relating to premises, are as follows: (dollars in thousands) Year ending December 31, 2013$1,77820141,57720151,41820161,2712017964Thereafter9,118Total lease commitments$16,126Net rental expense for all operating leases amounted to $2.2 million, $1.7 million, and $1.6 million for the years ended December 31, 2012, 2011 and 2010, respectively. |

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The entire disclosure for commitments and contingencies.
+ References
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