Investment Securities - Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities
Amortized Cost, Total available-for-sale securities	$ 331,910	$ 336,349
Unrealized Gains	5,075	7,766
Unrealized Losses	6,640	995
Fair Value, Total available-for-sale securities	330,345	343,120	[1]
Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year		10,005
Amortized Cost, After 1 but within 5 years	16,937	17,479
Amortized Cost	16,937	27,484
Unrealized Gains	0	44
Unrealized Losses	312	1
Fair Value, Within 1 year		10,020
Fair Value, After 1 but within 5 years	16,625	17,507
Fair Value	16,625	27,527
Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	18	119
Amortized Cost, After 1 but within 5 years	253	315
Amortized Cost, After 5 but within 10 years	17,651	10,371
Amortized Cost, After 10 years	100,277	94,319
Amortized Cost	118,199	105,124
Unrealized Gains	1,970	2,458
Unrealized Losses	1,150	325
Fair Value, Within 1 year	18	121
Fair Value, After 1 but within 5 years	267	341
Fair Value, After 5 but within 10 years	17,988	10,712
Fair Value, After 10 years	100,746	96,083
Fair Value	119,019	107,257
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	7,258	9,975
Amortized Cost, After 10 years	63,707	111,155
Amortized Cost	70,965	121,778
Unrealized Gains	942	1,110
Unrealized Losses	136	295
Fair Value, After 1 but within 5 years		650
Fair Value, After 5 but within 10 years	7,403	10,178
Fair Value, After 10 years	64,368	111,765
Fair Value	71,771	122,593
Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized Cost, After 5 but within 10 years	166	178
Amortized Cost, After 10 years	12,333	848
Amortized Cost	12,499	1,026
Unrealized Gains	17	19
Unrealized Losses	133	0
Fair Value, After 5 but within 10 years	165	178
Fair Value, After 10 years	12,218	867
Fair Value	12,383	1,045
State and municipal securities
Schedule of Available-for-sale Securities
Amortized Cost, Within 1 year	1,060	620
Amortized Cost, After 1 but within 5 years	5,870	5,734
Amortized Cost, After 5 but within 10 years	34,102	24,464
Amortized Cost, After 10 years	72,190	50,031
Amortized Cost	113,222	80,849
Unrealized Gains	2,097	4,089
Unrealized Losses	4,909	373
Fair Value, Within 1 year	1,085	626
Fair Value, After 1 but within 5 years	6,144	6,055
Fair Value, After 5 but within 10 years	34,871	26,150
Fair Value, After 10 years	68,310	51,734
Fair Value	110,410	84,565
Common and preferred stocks
Schedule of Available-for-sale Securities
Amortized Cost, Common and preferred stocks	88	88
Unrealized Gains	49	46
Unrealized Losses	0	1
Fair Value, Common and preferred stocks	137	133
Within 1 year | Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Unrealized Gains		15
Unrealized Losses		0
Within 1 year | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	0	2
Unrealized Losses	0	0
Within 1 year | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	25	6
Unrealized Losses	0	0
After 1 but within 5 years | Securities of U.S. government agencies
Schedule of Available-for-sale Securities
Unrealized Gains	0	29
Unrealized Losses	312	1
After 1 but within 5 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	14	26
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	274	321
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	337	341
Unrealized Losses	0	0
After 5 but within 10 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	148	206
Unrealized Losses	3	3
After 5 but within 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	0	0
Unrealized Losses	1	0
After 5 but within 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	1,223	1,698
Unrealized Losses	454	12
After 10 years | Government sponsored agencies - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Unrealized Gains	1,619	2,089
Unrealized Losses	1,150	325
After 10 years | Government sponsored agencies - Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	794	902
Unrealized Losses	133	292
After 10 years | Private label collateralized mortgage obligations
Schedule of Available-for-sale Securities
Unrealized Gains	17	19
Unrealized Losses	132	0
After 10 years | State and municipal securities
Schedule of Available-for-sale Securities
Unrealized Gains	575	2,064
Unrealized Losses	$ 4,455	$ 361

[1] Derived from audited consolidated financial statements