Fair Value Measurements (Details 2) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets:
Investment securities, available-for-sale	$ 791,727	$ 791,118
Trading account securities	0	205
Mortgages held for sale	9,825	13,604
U.S. Treasury and Federal agencies securities
Assets:
Investment securities, available-for-sale	389,669	373,503
U.S. States and political subdivisions securities
Assets:
Investment securities, available-for-sale	122,990	124,688
Mortgage-backed securities - Federal agencies
Assets:
Investment securities, available-for-sale	236,297	253,008
Corporate debt securities
Assets:
Investment securities, available-for-sale	34,383	31,932
Foreign government and other securities
Assets:
Investment securities, available-for-sale	809	811
Total debt securities
Assets:
Investment securities, available-for-sale	784,148	783,942
Marketable equity securities
Assets:
Investment securities, available-for-sale	7,579	7,176
Total
Assets:
Investment securities, available-for-sale	791,727	791,118
Mortgages held for sale	9,825	13,604
Level 1
Assets:
Investment securities, available-for-sale	27,458	26,984
Mortgages held for sale	0	0
Level 2
Assets:
Investment securities, available-for-sale	758,932	756,857
Mortgages held for sale	9,825	13,604
Level 3
Assets:
Investment securities, available-for-sale	5,337	7,277
Mortgages held for sale	0	0
Recurring \| Total
Assets:
Investment securities, available-for-sale	791,727	791,118
Trading account securities		205
Mortgages held for sale	9,825	13,604
Total	811,411	814,052
Liabilities:
Total	10,044	9,302
Recurring \| Total \| Interest rate swap contracts
Assets:
Accrued income and other assets	9,859	9,125
Liabilities:
Accrued expenses and other liabilities	10,044	9,302
Recurring \| Total \| U.S. Treasury and Federal agencies securities
Assets:
Investment securities, available-for-sale	389,669	373,503
Recurring \| Total \| U.S. States and political subdivisions securities
Assets:
Investment securities, available-for-sale	122,990	124,688
Recurring \| Total \| Mortgage-backed securities - Federal agencies
Assets:
Investment securities, available-for-sale	236,297	253,008
Recurring \| Total \| Corporate debt securities
Assets:
Investment securities, available-for-sale	34,383	31,932
Recurring \| Total \| Foreign government and other securities
Assets:
Investment securities, available-for-sale	809	811
Recurring \| Total \| Total debt securities
Assets:
Investment securities, available-for-sale	784,148	783,942
Recurring \| Total \| Marketable equity securities
Assets:
Investment securities, available-for-sale	7,579	7,176
Recurring \| Level 1
Assets:
Investment securities, available-for-sale	27,458	26,984
Trading account securities		205
Mortgages held for sale	0	0
Total	27,458	27,189
Liabilities:
Total	0	0
Recurring \| Level 1 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring \| Level 1 \| U.S. Treasury and Federal agencies securities
Assets:
Investment securities, available-for-sale	19,879	19,808
Recurring \| Level 1 \| U.S. States and political subdivisions securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 1 \| Mortgage-backed securities - Federal agencies
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 1 \| Corporate debt securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 1 \| Foreign government and other securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 1 \| Total debt securities
Assets:
Investment securities, available-for-sale	19,879	19,808
Recurring \| Level 1 \| Marketable equity securities
Assets:
Investment securities, available-for-sale	7,579	7,176
Recurring \| Level 2
Assets:
Investment securities, available-for-sale	758,932	756,857
Trading account securities		0
Mortgages held for sale	9,825	13,604
Total	778,616	779,586
Liabilities:
Total	10,044	9,302
Recurring \| Level 2 \| Interest rate swap contracts
Assets:
Accrued income and other assets	9,859	9,125
Liabilities:
Accrued expenses and other liabilities	10,044	9,302
Recurring \| Level 2 \| U.S. Treasury and Federal agencies securities
Assets:
Investment securities, available-for-sale	369,790	353,695
Recurring \| Level 2 \| U.S. States and political subdivisions securities
Assets:
Investment securities, available-for-sale	118,462	118,222
Recurring \| Level 2 \| Mortgage-backed securities - Federal agencies
Assets:
Investment securities, available-for-sale	236,297	253,008
Recurring \| Level 2 \| Corporate debt securities
Assets:
Investment securities, available-for-sale	34,383	31,932
Recurring \| Level 2 \| Foreign government and other securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 2 \| Total debt securities
Assets:
Investment securities, available-for-sale	758,932	756,857
Recurring \| Level 2 \| Marketable equity securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 3
Assets:
Investment securities, available-for-sale	5,337	7,277
Trading account securities		0
Mortgages held for sale	0	0
Total	5,337	7,277
Liabilities:
Total	0	0
Recurring \| Level 3 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring \| Level 3 \| U.S. Treasury and Federal agencies securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 3 \| U.S. States and political subdivisions securities
Assets:
Investment securities, available-for-sale	4,528	6,466
Recurring \| Level 3 \| Mortgage-backed securities - Federal agencies
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 3 \| Corporate debt securities
Assets:
Investment securities, available-for-sale	0	0
Recurring \| Level 3 \| Foreign government and other securities
Assets:
Investment securities, available-for-sale	809	811
Recurring \| Level 3 \| Total debt securities
Assets:
Investment securities, available-for-sale	5,337	7,277
Recurring \| Level 3 \| Marketable equity securities
Assets:
Investment securities, available-for-sale	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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