Fair Value Measurements (Details Textual) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Mortgage Loans on Real Estate [Line Items]
Impaired loans	$ 79,417,000		$ 68,800,000
Fair Value Measurements (Textual) [Abstract]
Carrying value of equity securities	7,400,000		7,368,000
ALL related to commercial and construction loans	3,700,000		4,400,000
Provision for loan losses related to commercial and construction loans	0	0
Foreclosed real estate	34,770,000		40,619,000
Charge-offs to the ALL	665,000		725,000
Write downs and net loss on sale related to foreclosed real estate	776,000		1,100,000
Loans Evaluated for Impairment [Member]
Mortgage Loans on Real Estate [Line Items]
Impaired loans	$ 83,200,000		$ 73,200,000

Allowance for loan losses related to non-performing commercial and construction loans.

No definition available.

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- Definition

Charge-offs to allowance for loan losses related to loans transferred to foreclosed real estate.

+ References

No definition available.

+ Details

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- Details

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- Definition

Provision for loan losses related to commercial and construction loans.

+ References

No definition available.

+ Details

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- Definition

Write downs and net loss on sale related to foreclosed real estate that were charged to non-interest expense.

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, this item represents equity securities categorized neither as held-to-maturity nor trading. Equity securities represent ownership interests or the right to acquire ownership interests in corporations and other legal entities which ownership interest is represented by shares of common or preferred stock (which is not mandatorily redeemable or redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Unrealized gains and losses related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 86-40

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 3

-Subparagraph c

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- Definition

Reflects the adjusted carrying amount of loans for which it is probable, based on current facts and circumstances, that a creditor will not initially be able to collect all amounts due according to the contractual terms of the loan agreement, or will not recover the previously reported carrying amount of the loan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-Subparagraph a

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

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph j(ii)

-Subsection I

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph f

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 11

-Paragraph 2, 9, 10, 11

-IssueDate 2006-05-01

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

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