Investment Securities - Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities
Amortized Cost, Total available-for-sale securities	$ 336,349	$ 324,172
Unrealized Gains	7,766	7,372
Unrealized Losses	995	1,122
Fair Value, Total available-for-sale securities	343,120	330,422
Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	10,005	9,988
Amortized Cost, After 1 but within 5 years	17,479	13,622
Amortized Cost	27,484	23,610
Unrealized Gains	44	116
Unrealized Losses	1	0
Fair Value, Within 1 year	10,020	10,039
Fair Value, After 1 but within 5 years	17,507	13,687
Fair Value	27,527	23,726
Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	119
Amortized Cost, After 1 but within 5 years	315	476
Amortized Cost, After 5 but within 10 years	10,371	3,481
Amortized Cost, After 10 years	94,319	60,388
Amortized Cost	105,124	64,345
Unrealized Gains	2,458	1,258
Unrealized Losses	325	393
Fair Value, Within 1 year	121
Fair Value, After 1 but within 5 years	341	494
Fair Value, After 5 but within 10 years	10,712	3,762
Fair Value, After 10 years	96,083	60,954
Fair Value	107,257	65,210
Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized Cost, After 1 but within 5 years	648
Amortized Cost, After 5 but within 10 years	9,975	13,986
Amortized Cost, After 10 years	111,155	150,915
Amortized Cost	121,778	164,901
Unrealized Gains	1,110	1,719
Unrealized Losses	295	592
Fair Value, After 1 but within 5 years	650
Fair Value, After 5 but within 10 years	10,178	14,464
Fair Value, After 10 years	111,765	151,564
Fair Value	122,593	166,028
Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized Cost, After 5 but within 10 years	178	275
Amortized Cost, After 10 years	848	1,028
Amortized Cost	1,026	1,303
Unrealized Gains	19	10
Unrealized Losses	0	57
Fair Value, After 5 but within 10 years	178	285
Fair Value, After 10 years	867	971
Fair Value	1,045	1,256
State and municipal securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	620	618
Amortized Cost, After 1 but within 5 years	5,734	6,575
Amortized Cost, After 5 but within 10 years	24,464	21,252
Amortized Cost, After 10 years	50,031	40,455
Amortized Cost	80,849	68,900
Unrealized Gains	4,089	4,246
Unrealized Losses	373	28
Fair Value, Within 1 year	626	623
Fair Value, After 1 but within 5 years	6,055	6,922
Fair Value, After 5 but within 10 years	26,150	22,872
Fair Value, After 10 years	51,734	42,701
Fair Value	84,565	73,118
Common and preferred stocks
Schedule of Available-for-sale Securities
Amortized Cost, Common and preferred stocks	88	1,113
Unrealized Gains	46	23
Unrealized Losses	1	52
Fair Value, Common and preferred stocks	133	1,084
Within 1 year | Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Unrealized Gains	15	51
Unrealized Losses	0	0
Within 1 year | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	2
Unrealized Losses	0
Within 1 year | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	6	5
Unrealized Losses	0	0
After 1 but within 5 years | Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Unrealized Gains	29	65
Unrealized Losses	1	0
After 1 but within 5 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	26	18
Unrealized Losses	0	0
After 1 but within 5 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	2
Unrealized Losses	0
After 1 but within 5 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	321	347
Unrealized Losses	0	0
After 5 but within 10 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	341	281
Unrealized Losses	0	0
After 5 but within 10 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	206	478
Unrealized Losses	3	0
After 5 but within 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	0	10
Unrealized Losses	0	0
After 5 but within 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	1,698	1,639
Unrealized Losses	12	19
After 10 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	2,089	959
Unrealized Losses	325	393
After 10 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	902	1,241
Unrealized Losses	292	592
After 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	19	0
Unrealized Losses	0	57
After 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	2,064	2,255
Unrealized Losses	$ 361	$ 9