Investment Securities - Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Available-for-Sale:
Amortized Cost	$ 326,354	$ 260,728
Unrealized Gains	3,985	3,657
Unrealized Losses	2,599	6,144
Available-for-sale, at fair value	327,740	258,241
Investment Securities Held-to-Maturity:
Amortized Cost	23,843	16,323
Unrealized Gains	120	159
Unrealized Losses	215	286
Fair Value	23,748	16,196
U.S. Treasury Notes [Member]
Available-for-Sale:
Amortized Cost	60,677	13,184
Unrealized Gains	206	0
Unrealized Losses	162	290
Available-for-sale, at fair value	60,721	12,894
US Agency Notes [Member]
Available-for-Sale:
Amortized Cost	118,416	110,248
Unrealized Gains	431	141
Unrealized Losses	1,525	3,714
Available-for-sale, at fair value	117,322	106,675
US Agency Mortgage-Backed Securities [Member]
Available-for-Sale:
Amortized Cost	41,979	40,602
Unrealized Gains	540	555
Unrealized Losses	369	848
Available-for-sale, at fair value	42,150	40,309
Investment Securities Held-to-Maturity:
Fair Value	0
Certificates of Deposit with Other Banks [Member]
Available-for-Sale:
Amortized Cost	3,078	1,492
Unrealized Gains	15	9
Unrealized Losses	0	0
Available-for-sale, at fair value	3,093	1,501
Non-Taxable [Member]
Available-for-Sale:
Amortized Cost	83,067	74,185
Unrealized Gains	2,044	2,116
Unrealized Losses	374	968
Available-for-sale, at fair value	84,737	75,333
Investment Securities Held-to-Maturity:
Amortized Cost	23,443	15,923
Unrealized Gains	119	159
Unrealized Losses	215	285
Fair Value	23,347	15,797
Taxable Municipal Securities [Member]
Available-for-Sale:
Amortized Cost	15,177	17,020
Unrealized Gains	406	503
Unrealized Losses	126	214
Available-for-sale, at fair value	15,457	17,309
Investment Securities Held-to-Maturity:
Amortized Cost	400	400
Unrealized Gains	1	0
Unrealized Losses	0	1
Fair Value	401	399
Mutual Funds [Member]
Available-for-Sale:
Amortized Cost	2,436	2,419
Unrealized Gains	0	0
Unrealized Losses	17	39
Available-for-sale, at fair value	2,419	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	1	6
Available-for-sale, at fair value	49	147
Investment Securities Held-to-Maturity:
Fair Value	0
Equity Securities [Member]
Available-for-Sale:
Amortized Cost	1,474	1,429
Unrealized Gains	343	329
Unrealized Losses	25	65
Available-for-sale, at fair value	1,792	1,693
Investment Securities Held-to-Maturity:
Fair Value	$ 0