Investment Securities - Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Available-for-Sale:
Amortized Cost	$ 311,096	$ 260,728
Unrealized Gains	3,642	3,657
Unrealized Losses	4,675	6,144
Available-for-sale, at fair value	310,063	258,241
Investment Securities Held-to-Maturity:
Amortized Cost	16,467	16,323
Unrealized Gains	117	159
Unrealized Losses	258	286
Fair Value	16,326	16,196
U.S. Treasury Notes [Member]
Available-for-Sale:
Amortized Cost	35,477	13,184
Unrealized Gains	1	0
Unrealized Losses	306	290
Available-for-sale, at fair value	35,172	12,894
US Agency Notes [Member]
Available-for-Sale:
Amortized Cost	125,001	110,248
Unrealized Gains	152	141
Unrealized Losses	2,692	3,714
Available-for-sale, at fair value	122,461	106,675
US Agency Mortgage-Backed Securities [Member]
Available-for-Sale:
Amortized Cost	44,041	40,602
Unrealized Gains	496	555
Unrealized Losses	708	848
Available-for-sale, at fair value	43,829	40,309
Investment Securities Held-to-Maturity:
Fair Value	0
Certificates of Deposit with Other Banks [Member]
Available-for-Sale:
Amortized Cost	3,079	1,492
Unrealized Gains	16	9
Unrealized Losses	0	0
Available-for-sale, at fair value	3,095	1,501
Non-Taxable [Member]
Available-for-Sale:
Amortized Cost	83,108	74,185
Unrealized Gains	2,136	2,116
Unrealized Losses	758	968
Available-for-sale, at fair value	84,486	75,333
Investment Securities Held-to-Maturity:
Amortized Cost	16,067	15,923
Unrealized Gains	117	159
Unrealized Losses	258	285
Fair Value	15,926	15,797
Taxable Municipal Securities [Member]
Available-for-Sale:
Amortized Cost	16,439	17,020
Unrealized Gains	533	503
Unrealized Losses	141	214
Available-for-sale, at fair value	16,831	17,309
Investment Securities Held-to-Maturity:
Amortized Cost	400	400
Unrealized Gains	0	0
Unrealized Losses	0	1
Fair Value	400	399
Mutual Funds [Member]
Available-for-Sale:
Amortized Cost	2,427	2,419
Unrealized Gains	0	0
Unrealized Losses	32	39
Available-for-sale, at fair value	2,395	2,380
Investment Securities Held-to-Maturity:
Fair Value	0
Trust Preferred Securities [Member]
Available-for-Sale:
Amortized Cost	50	149
Unrealized Gains	0	4
Unrealized Losses	0	6
Available-for-sale, at fair value	50	147
Investment Securities Held-to-Maturity:
Fair Value	0
Equity Securities [Member]
Available-for-Sale:
Amortized Cost	1,474	1,429
Unrealized Gains	308	329
Unrealized Losses	38	65
Available-for-sale, at fair value	1,744	1,693
Investment Securities Held-to-Maturity:
Fair Value	$ 0