Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Assets [Abstract]
Trading securities		$ 180	$ 203
Securities available for sale		557,695	533,178
Liabilities [Abstract]
Subordinated debentures		35,569	35,569
Reciprocal deposits included in deposits with no stated maturity		12,500	13,600
Reciprocal deposits included in deposits with stated maturity		36,500	40,100
Recorded Book Balance [Member]
Assets [Abstract]
Cash and due from banks		44,272	48,326
Interest bearing deposits		14,045	25,690
Interest bearing deposits - time		10,853	13,561
Trading securities		180	203
Securities available for sale		557,695	533,178
Federal Home Loan Bank and Federal Reserve Bank Stock		15,146	19,919
Net loans and loans held for sale		1,455,939	1,407,634
Accrued interest receivable		6,059	5,995
Derivative financial instruments		1,100	619
Liabilities [Abstract]
Deposits with no stated maturity	[1]	1,594,948	1,534,175
Deposits with stated maturity	[1]	366,469	390,127
Other borrowings		12,325	12,470
Subordinated debentures		35,569	35,569
Accrued interest payable		392	380
Derivative financial instruments		222	366
Fair Value [Member]
Assets [Abstract]
Cash and due from banks		44,272	48,326
Interest bearing deposits		14,045	25,690
Interest bearing deposits - time		10,892	13,585
Trading securities		180	203
Securities available for sale		557,695	533,178
Net loans and loans held for sale		1,435,236	1,394,424
Accrued interest receivable		6,059	5,995
Derivative financial instruments		1,100	619
Liabilities [Abstract]
Deposits with no stated maturity	[1]	1,594,948	1,534,175
Deposits with stated maturity	[1]	365,081	389,139
Other borrowings		14,165	14,560
Subordinated debentures		24,117	23,328
Accrued interest payable		392	380
Derivative financial instruments		222	366
Quoted Prices in Active Markets for Identical Assets, (Level 1) [Member]
Assets [Abstract]
Cash and due from banks		44,272	48,326
Interest bearing deposits		14,045	25,690
Interest bearing deposits - time		0	0
Trading securities		180	203
Securities available for sale		0	0
Net loans and loans held for sale		0	0
Accrued interest receivable		1	2
Derivative financial instruments		0	0
Liabilities [Abstract]
Deposits with no stated maturity	[1]	1,594,948	1,534,175
Deposits with stated maturity	[1]	0	0
Other borrowings		0	0
Subordinated debentures		0	0
Accrued interest payable		20	21
Derivative financial instruments		0	0
Significant Other Observable Inputs, (Level 2) [Member]
Assets [Abstract]
Cash and due from banks		0	0
Interest bearing deposits		0	0
Interest bearing deposits - time		10,892	13,585
Trading securities		0	0
Securities available for sale		557,695	533,178
Net loans and loans held for sale		30,518	23,662
Accrued interest receivable		1,647	1,599
Derivative financial instruments		1,100	619
Liabilities [Abstract]
Deposits with no stated maturity	[1]	0	0
Deposits with stated maturity	[1]	365,081	389,139
Other borrowings		14,165	14,560
Subordinated debentures		24,117	23,328
Accrued interest payable		372	359
Derivative financial instruments		222	366
Significant Unobservable Inputs, (Level 3) [Member]
Assets [Abstract]
Cash and due from banks		0	0
Interest bearing deposits		0	0
Interest bearing deposits - time		0	0
Trading securities		0	0
Securities available for sale		0	0
Net loans and loans held for sale		1,404,718	1,370,762
Accrued interest receivable		4,411	4,394
Derivative financial instruments		0	0
Liabilities [Abstract]
Deposits with no stated maturity	[1]	0	0
Deposits with stated maturity	[1]	0	0
Other borrowings		0	0
Subordinated debentures		0	0
Accrued interest payable		0	0
Derivative financial instruments		$ 0	$ 0

[1] Deposits with no stated maturity include reciprocal deposits with a recorded book balance of $12.5 million and $13.6 million at June 30, 2015 and December 31, 2014, respectively. Deposits with a stated maturity include reciprocal deposits with a recorded book balance of $36.5 million and $40.1 million at June 30, 2015 and December 31, 2014, respectively.