Fair Value Disclosures - Assets, Liabilities and Off-Balance Sheet Items Not Measured at Fair Value (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Deposits:
Time deposits	$ 306,520	$ 331,511	[1]
Carrying Amount [Member]
Assets:
Cash and short-term interest-earning assets	84,562	146,112
Held-to-maturity securities	69,636	69,845
Loans held for sale	3,606	4,530
Net loans and leases held for investment	1,462,153	1,457,116
Mortgage servicing rights	4,723
Other real estate owned	3,616
Total assets	1,628,296	1,677,603
Deposits:
Demand and savings deposits, non-maturity	1,508,090	1,533,822
Time deposits	306,520	331,511
Total deposits	1,814,610	1,865,333
Short-term borrowings	104,276	96,282
Long-term borrowings	20,619	20,994
Total Liabilities	1,939,505	1,982,609
Off-Balance-Sheet:
Commitments to extend credit
Fair Value [Member]
Assets:
Cash and short-term interest-earning assets	84,562	146,112
Held-to-maturity securities	71,099	71,327
Loans held for sale	3,676	4,653
Net loans and leases held for investment	1,484,042	1,478,966
Mortgage servicing rights	5,018
Other real estate owned	3,616
Total assets	1,652,013	1,701,058
Deposits:
Demand and savings deposits, non-maturity	1,508,090	1,533,822
Time deposits	307,652	334,164
Total deposits	1,815,742	1,867,986
Short-term borrowings	101,495	94,066
Long-term borrowings	20,591	20,965
Total Liabilities	1,937,828	1,983,017
Off-Balance-Sheet:
Commitments to extend credit	(1,301)	(1,286)
Fair Value [Member] | Level 1 [Member]
Assets:
Cash and short-term interest-earning assets	84,562	146,112
Held-to-maturity securities
Loans held for sale
Net loans and leases held for investment
Mortgage servicing rights
Other real estate owned
Total assets	84,562	146,112
Deposits:
Demand and savings deposits, non-maturity	1,508,090	1,533,822
Time deposits
Total deposits	1,508,090	1,533,822
Short-term borrowings
Long-term borrowings
Total Liabilities	1,508,090	1,533,822
Off-Balance-Sheet:
Commitments to extend credit
Fair Value [Member] | Level 2 [Member]
Assets:
Cash and short-term interest-earning assets
Held-to-maturity securities	71,099	71,327
Loans held for sale	3,676	4,653
Net loans and leases held for investment
Mortgage servicing rights	5,018
Other real estate owned	3,616
Total assets	83,409	75,980
Deposits:
Demand and savings deposits, non-maturity
Time deposits	307,652	334,164
Total deposits	307,652	334,164
Short-term borrowings	101,495	94,066
Long-term borrowings	20,591	20,965
Total Liabilities	429,738	449,195
Off-Balance-Sheet:
Commitments to extend credit	(1,301)	(1,286)
Fair Value [Member] | Level 3 [Member]
Assets:
Cash and short-term interest-earning assets
Held-to-maturity securities
Loans held for sale
Net loans and leases held for investment	1,484,042	1,478,966
Mortgage servicing rights
Other real estate owned
Total assets	1,484,042	1,478,966
Deposits:
Demand and savings deposits, non-maturity
Time deposits
Total deposits
Short-term borrowings
Long-term borrowings
Total Liabilities
Off-Balance-Sheet:
Commitments to extend credit

[1] Note: The consolidated balance sheet at December 31, 2012 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U. S. generally accepted accounting principles for complete financial statements. See accompanying notes to the unaudited consolidated financial statements.