Loans and Allowance - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 6,392us-gaap_LoansReceivableHeldForSaleNet		$ 7,235us-gaap_LoansReceivableHeldForSaleNet
Loans - allowance for loan losses	62,801	69,583	63,964	67,870
Decrease in allowance for loan losses	1,163
Allowance for impaired financing receivables change	2,762
Impaired financing receivable, allowance	4,556	1,794	2,769
Allowance for loan losses, write-offs (recoveries)	1,163	(1,713)
Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans - allowance for loan losses	13,269	13,908	13,152	15,077
Impaired financing receivable, allowance	554		194
Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired financing receivable, allowance	$ 1,302		$ 1,120
Percentage of troubled debt restructured loans	54.00%

Financing Receivable, Modifications, Post-Modification, Loans as Percentage of Troubled Debt Restructured Loans

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- Definition

Impaired Financing Receivable Related Allowance, Period Increase (Decrease)

+ References

No definition available.

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

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- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB

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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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-Number Topic 6

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- Definition

Amount classified as loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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