Loans and Allowance - Allowance for Credit Losses and Loan Portfolio by Loan Segment (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance balances - Individually evaluated for impairment	$ 1,351	$ 1,354
Allowance balances - Collectively evaluated for impairment	67,789	66,287
Allowance balances - Loans acquired with deteriorated credit quality	443	229
Total Allowance for Loan Losses	69,583	67,870	68,537	69,366
Loan balances - Individually evaluated for impairment	42,120	42,067
Loan balances - Collectively evaluated for impairment	3,497,649	3,511,501
Loan balances - Loans acquired with deteriorated credit quality	76,858	78,841
Loans	3,616,627	3,632,409
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance balances - Individually evaluated for impairment	556	585
Allowance balances - Collectively evaluated for impairment	30,004	26,493
Allowance balances - Loans acquired with deteriorated credit quality	347	98
Total Allowance for Loan Losses	30,907	27,176	25,371	25,913
Loan balances - Individually evaluated for impairment	10,422	10,240
Loan balances - Collectively evaluated for impairment	890,590	882,794
Loan balances - Loans acquired with deteriorated credit quality	7,651	7,548
Loans	908,663	900,582
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance balances - Individually evaluated for impairment	795	763
Allowance balances - Collectively evaluated for impairment	21,467	22,208
Allowance balances - Loans acquired with deteriorated credit quality	96	131
Total Allowance for Loan Losses	22,358	23,102	24,978	26,703
Loan balances - Individually evaluated for impairment	28,864	29,007
Loan balances - Collectively evaluated for impairment	1,665,466	1,690,285
Loan balances - Loans acquired with deteriorated credit quality	67,522	69,599
Loans	1,761,852	1,788,891
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance balances - Collectively evaluated for impairment	2,410	2,515
Total Allowance for Loan Losses	2,410	2,515	2,689	2,593
Loan balances - Collectively evaluated for impairment	61,742	69,783
Loans	61,742	69,783
Residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance balances - Individually evaluated for impairment		6
Allowance balances - Collectively evaluated for impairment	13,908	15,071
Total Allowance for Loan Losses	13,908	15,077	15,479	14,157
Loan balances - Individually evaluated for impairment	2,834	2,820
Loan balances - Collectively evaluated for impairment	878,473	867,094
Loan balances - Loans acquired with deteriorated credit quality	1,685	1,694
Loans	882,992	871,608
Finance Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Allowance for Loan Losses			20
Loan balances - Collectively evaluated for impairment	1,378	1,545
Loans	$ 1,378	$ 1,545

Loans and Leases Receivable

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- Definition

The balance of financing receivables that were acquired with deteriorated credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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The valuation allowance for financing receivables acquired with deteriorated credit quality.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

-Publisher FASB

-Name Accounting Standards Codification

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The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.7(d))

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