Loans and Allowance for Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Impaired loans segregated by class of loans
Unpaid Principal Balance	$ 49,972	$ 24,426
Recorded Investment with Allowance	45,173	21,187
Related Allowance	4,492	3,014
Average Recorded Investment	42,519	24,777
Non-residential real estate [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	28,098	9,311
Recorded Investment with Allowance	26,682	8,576
Related Allowance	2,211	952
Average Recorded Investment	23,283	9,583
Residential real estate [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	5,469	5,526
Recorded Investment with Allowance	4,913	4,798
Related Allowance	1,328	1,331
Average Recorded Investment	5,185	6,040
Non-consumer non-real estate [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	1,949	1,535
Recorded Investment with Allowance	1,539	1,214
Related Allowance	439	282
Average Recorded Investment	1,641	1,584
Consumer non-real estate [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	419	196
Recorded Investment with Allowance	398	161
Related Allowance	87	24
Average Recorded Investment	357	195
Other loans [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	2,957	3,345
Recorded Investment with Allowance	2,561	3,247
Related Allowance	344	405
Average Recorded Investment	2,323	4,086
Acquired loans [Member]
Impaired loans segregated by class of loans
Unpaid Principal Balance	11,080	4,513
Recorded Investment with Allowance	9,080	3,191
Related Allowance	83	20
Average Recorded Investment	$ 9,730	$ 3,289

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

+ Details

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

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