Borrowings and Borrowings Availability (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Total borrowings	$ 46,394	$ 133,894
Unamortized fair market value adjustment recorded in acquisition		31
Borrowings	46,394	133,925
Weighted average interest rate	2.28%	1.74%
Trust Preferred Securities 1
Maturity date	Jan. 23, 2034	Jan. 23, 2034
Issuer	Issued by First Bancorp Capital Trusts II and III, which are unconsolidated subsidiaries of the Company
Call Feature	Quarterly by Company beginning 1/23/09	Quarterly by Company beginning 1/23/09
Earliest date of call feature	Jan. 23, 2009	Jan. 23, 2009
Borrowings	20,620	20,620
Effective percentage	3.01%	3.13%
Variable rate description	3 month LIBOR	3 month LIBOR
Variable rate basis spread	2.70%	2.70%
Trust Preferred Securities 2
Maturity date	Jun. 15, 2036	Jun. 15, 2036
Issuer	Issued by First Bancorp Capital Trust IV, an unconsolidated subsidiary of the Company
Call Feature	Quarterly by Company beginning 6/15/11	Quarterly by Company beginning 6/15/11
Earliest date of call feature	Jun. 15, 2011	Jun. 15, 2011
Borrowings	25,774	25,774
Effective percentage	1.70%	1.94%
Variable rate description	3 month LIBOR	3 month LIBOR
Variable rate basis spread	1.39%	1.39%
FHLB Term Note 1
Maturity date		Apr. 20, 2012
Call Feature		Quarterly by FHLB, beginning 4/20/09
Earliest date of call feature		Apr. 20, 2009
Borrowings		7,500
Stated percentage		4.51%
FHLB Term Note 2
Maturity date		Jun. 28, 2012
Call Feature		None
Borrowings		15,000
Stated percentage		0.69%
FHLB Term Note 3
Maturity date		Dec. 28, 2012
Call Feature		None
Borrowings		7,500
Stated percentage		0.91%
FHLB Term Note 4
Maturity date		Jun. 28, 2013
Call Feature		None
Borrowings		15,000
Stated percentage		0.72%
FHLB Term Note 5
Maturity date		Dec. 30, 2013
Call Feature		None
Borrowings		7,500
Stated percentage		1.50%
FHLB Term Note 6
Maturity date		Jan. 13, 2014
Call Feature		None
Borrowings		20,000
Stated percentage		1.38%
FHLB Term Note 7
Maturity date		Jun. 30, 2014
Call Feature		None
Borrowings		$ 15,000
Stated percentage		1.21%

The amount of unamortized fair market value adjustment recorded in an acquisition.

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

Earliest date before maturity when the issuer can call the outstanding debt instrument for repayment or conversion to equity, in CCYY-MM-DD format.

+ References

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- Definition

Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

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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

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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- Definition

Identification of the contractual issuer of the debt instrument (for example, a subsidiary of the reporting entity).

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of debt outstanding by type or by instrument at that time.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

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