Junior Subordinated Debt (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended
Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 F.N.B. Statutory Trust I [Member]	Mar. 31, 2012 F.N.B. Statutory Trust II [Member]	Mar. 31, 2012 Omega Financial Capital Trust I [Member]	Mar. 31, 2012 Sun Bancorp Statutory Trust I [Member]
Subordinated Borrowing [Line Items]
Percent of the common equity of each Trust owned by the Corporation	100.00%
Trust preferred securities			$ 125,000	$ 21,500	$ 36,000	$ 16,500
Common securities			3,866	665	1,114	511
Junior subordinated debt	$ 203,980	$ 203,967	$ 128,866	$ 22,165	$ 35,938	$ 17,011
Stated maturity date			Mar. 31, 2033	Jun. 15, 2036	Oct. 18, 2034	Feb. 22, 2031
Interest rate			3.83%	2.12%	2.75%	10.20%
Description of variable rate			% variable; LIBOR plus 325 basis points	% variable; LIBOR plus 165 basis points	% variable; LIBOR plus 219 basis points
Basis points			3.25%	1.65%	2.19%
Number of unconsolidated subsidiary trusts	4

Number of unconsolidated subsidiary trusts.

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- Definition

Percentage Of Each Trust Common Equity Owned By Corporation

+ References

No definition available.

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- Definition

Subsidiary Trust Common Shares Issued To Parent

+ References

No definition available.

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- Definition

Trust preferred securities.

+ References

No definition available.

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- Definition

The percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

The effective interest rate at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-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

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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