Loans (Summary of Recorded Investment of Commercial Loans by Risk Rating Categories) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	$ 2,364,870	$ 2,264,820	$ 2,129,234
Commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,091,894	1,002,722	915,352
Real estate commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,172,347	1,161,861	1,119,655
Real estate construction [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	73,448	62,689	54,538
Land development [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	27,181	37,548	39,689
Originated Portfolio [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	2,070,290	1,927,956	1,743,047
Originated Portfolio [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,886,835	1,736,870	1,552,471
Originated Portfolio [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	70,990	83,883	64,710
Originated Portfolio [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	69,298	49,541	68,017
Originated Portfolio [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	41,358	51,286	54,229
Originated Portfolio [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,809	6,376	3,620
Originated Portfolio [Member] | Commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	986,910	896,610	787,250
Originated Portfolio [Member] | Commercial [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	919,985	827,112	727,713
Originated Portfolio [Member] | Commercial [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	26,848	38,066	23,651
Originated Portfolio [Member] | Commercial [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	29,025	16,831	23,213
Originated Portfolio [Member] | Commercial [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	9,693	12,540	12,235
Originated Portfolio [Member] | Commercial [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,359	2,061	438
Originated Portfolio [Member] | Real estate commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,003,572	956,165	890,724
Originated Portfolio [Member] | Real estate commercial [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	897,960	846,901	773,312
Originated Portfolio [Member] | Real estate commercial [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	43,650	45,261	37,144
Originated Portfolio [Member] | Real estate commercial [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	33,464	26,343	38,577
Originated Portfolio [Member] | Real estate commercial [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	28,048	33,345	38,509
Originated Portfolio [Member] | Real estate commercial [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	450	4,315	3,182
Originated Portfolio [Member] | Real estate construction [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	60,874	49,123	36,605
Originated Portfolio [Member] | Real estate construction [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	59,575	47,847	35,496
Originated Portfolio [Member] | Real estate construction [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	58	59	0
Originated Portfolio [Member] | Real estate construction [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,058	0	701
Originated Portfolio [Member] | Real estate construction [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	183	1,217	408
Originated Portfolio [Member] | Real estate construction [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Originated Portfolio [Member] | Land development [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	18,934	26,058	28,468
Originated Portfolio [Member] | Land development [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	9,315	15,010	15,950
Originated Portfolio [Member] | Land development [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	434	497	3,915
Originated Portfolio [Member] | Land development [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	5,751	6,367	5,526
Originated Portfolio [Member] | Land development [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	3,434	4,184	3,077
Originated Portfolio [Member] | Land development [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	294,580	336,864	386,187
Acquired Portfolio [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	271,403	303,765	338,535
Acquired Portfolio [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	8,011	14,362	25,718
Acquired Portfolio [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	9,419	11,846	11,009
Acquired Portfolio [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	5,747	6,891	10,925
Acquired Portfolio [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	104,984	106,112	128,102
Acquired Portfolio [Member] | Commercial [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	100,241	93,281	107,624
Acquired Portfolio [Member] | Commercial [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	2,315	8,225	13,158
Acquired Portfolio [Member] | Commercial [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	699	2,169	1,611
Acquired Portfolio [Member] | Commercial [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,729	2,437	5,709
Acquired Portfolio [Member] | Commercial [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Real estate commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	168,775	205,696	228,931
Acquired Portfolio [Member] | Real estate commercial [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	152,906	188,499	205,091
Acquired Portfolio [Member] | Real estate commercial [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	5,696	5,900	12,560
Acquired Portfolio [Member] | Real estate commercial [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	8,720	9,677	9,398
Acquired Portfolio [Member] | Real estate commercial [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,453	1,620	1,882
Acquired Portfolio [Member] | Real estate commercial [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Real estate construction [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	12,574	13,566	17,933
Acquired Portfolio [Member] | Real estate construction [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	12,574	13,566	17,933
Acquired Portfolio [Member] | Real estate construction [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Real estate construction [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Real estate construction [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Real estate construction [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Land development [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	8,247	11,490	11,221
Acquired Portfolio [Member] | Land development [Member] | Risk Grades 1-5 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	5,682	8,419	7,887
Acquired Portfolio [Member] | Land development [Member] | Risk Grade 6 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	237	0
Acquired Portfolio [Member] | Land development [Member] | Risk Grade 7 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	0	0	0
Acquired Portfolio [Member] | Land development [Member] | Risk Grade 8 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	2,565	2,834	3,334
Acquired Portfolio [Member] | Land development [Member] | Risk Grade 9 [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	$ 0	$ 0	$ 0