Investment Securities - Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities
Amortized Cost, Total available-for-sale securities	$ 302,718	$ 324,172
Unrealized Gains	8,352	7,372
Unrealized Losses	514	1,122
Fair Value, Total available-for-sale securities	310,556	330,422	[1]
Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	20,008	9,988
Amortized Cost, After 1 but within 5 years	12,779	13,622
Amortized Cost	32,787	23,610
Unrealized Gains	82	116
Unrealized Losses	0	0
Fair Value, Within 1 year	20,052	10,039
Fair Value, After 1 but within 5 years	12,817	13,687
Fair Value	32,869	23,726
Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	67
Amortized Cost, After 1 but within 5 years	490	476
Amortized Cost, After 5 but within 10 years	11,526	3,481
Amortized Cost, After 10 years	68,847	60,388
Amortized Cost	80,930	64,345
Unrealized Gains	2,346	1,258
Unrealized Losses	12	393
Fair Value, Within 1 year	68
Fair Value, After 1 but within 5 years	518	494
Fair Value, After 5 but within 10 years	11,871	3,762
Fair Value, After 10 years	70,807	60,954
Fair Value	83,264	65,210
Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized Cost, After 1 but within 5 years	1,743
Amortized Cost, After 5 but within 10 years	10,332	13,986
Amortized Cost, After 10 years	124,469	150,915
Amortized Cost	136,544	164,901
Unrealized Gains	1,389	1,719
Unrealized Losses	450	592
Fair Value, After 1 but within 5 years	1,750
Fair Value, After 5 but within 10 years	10,654	14,464
Fair Value, After 10 years	125,079	151,564
Fair Value	137,483	166,028
Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized Cost, After 5 but within 10 years	190	275
Amortized Cost, After 10 years	853	1,028
Amortized Cost	1,043	1,303
Unrealized Gains	23	10
Unrealized Losses	7	57
Fair Value, After 5 but within 10 years	183	285
Fair Value, After 10 years	876	971
Fair Value	1,059	1,256
State and municipal securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	720	618
Amortized Cost, After 1 but within 5 years	5,738	6,575
Amortized Cost, After 5 but within 10 years	19,025	21,252
Amortized Cost, After 10 years	24,816	40,455
Amortized Cost	50,299	68,900
Unrealized Gains	4,470	4,246
Unrealized Losses	0	28
Fair Value, Within 1 year	731	623
Fair Value, After 1 but within 5 years	6,105	6,922
Fair Value, After 5 but within 10 years	20,673	22,872
Fair Value, After 10 years	27,260	42,701
Fair Value	54,769	73,118
Common and preferred stocks
Schedule of Available-for-sale Securities
Amortized Cost, Common and preferred stocks	1,115	1,113
Unrealized Gains	42	23
Unrealized Losses	45	52
Fair Value, Common and preferred stocks	1,112	1,084
Within 1 year | Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Unrealized Gains	44	51
Unrealized Losses	0	0
Within 1 year | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	1
Unrealized Losses	0
Within 1 year | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	11	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	38	65
Unrealized Losses	0	0
After 1 but within 5 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	28	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	7
Unrealized Losses	0
After 1 but within 5 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	367	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	345	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	322	478
Unrealized Losses	0	0
After 5 but within 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	0	10
Unrealized Losses	7	0
After 5 but within 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	1,648	1,639
Unrealized Losses	0	19
After 10 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	1,972	959
Unrealized Losses	12	393
After 10 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	1,060	1,241
Unrealized Losses	450	592
After 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	23	0
Unrealized Losses	0	57
After 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	2,444	2,255
Unrealized Losses	$ 0	$ 9

[1] Derived from audited consolidated financial statements