Loans (Summary of the Aging Status of the Recorded Investment in Loans by Portfolio Segment/Class) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Originated Portfolio [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	$ 22,816	$ 20,595	$ 14,824
Financing receivable, recorded investment 61 to 89 days past due	3,625	3,352	4,637
Financing receivable, recorded investment accruing loans past due 90 days or more	801	2,073	1,395
Financing receivable, recorded investment, Nonaccrual loans	53,440	50,644	57,687
Financing receivable recorded investment, Total past due	80,682	76,664	78,543
Financing receivable, recorded investment, current	4,967,980	4,913,403	4,385,922
Financing receivable, recorded investment, Total loans	5,048,662	4,990,067	4,464,465
Originated Portfolio [Member] | Commercial [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	10,121	4,033	6,003
Financing receivable, recorded investment 61 to 89 days past due	729	743	1,832
Financing receivable, recorded investment accruing loans past due 90 days or more	52	170	43
Financing receivable, recorded investment, Nonaccrual loans	18,904	16,418	18,251
Financing receivable recorded investment, Total past due	29,806	21,364	26,129
Financing receivable, recorded investment, current	1,235,101	1,234,534	1,104,992
Financing receivable, recorded investment, Total loans	1,264,907	1,255,898	1,131,121
Originated Portfolio [Member] | Real estate commercial [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	7,238	7,515	4,094
Financing receivable, recorded investment 61 to 89 days past due	2,267	1,383	1,098
Financing receivable, recorded investment accruing loans past due 90 days or more	148	0	730
Financing receivable, recorded investment, Nonaccrual loans	24,766	24,966	27,568
Financing receivable recorded investment, Total past due	34,419	33,864	33,490
Financing receivable, recorded investment, current	1,237,929	1,170,562	1,095,228
Financing receivable, recorded investment, Total loans	1,272,348	1,204,426	1,128,718
Originated Portfolio [Member] | Real estate construction [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	340	262	18
Financing receivable, recorded investment 61 to 89 days past due	0	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	0	0	0
Financing receivable, recorded investment, Nonaccrual loans	663	162	160
Financing receivable recorded investment, Total past due	1,003	424	178
Financing receivable, recorded investment, current	94,920	138,316	72,227
Financing receivable, recorded investment, Total loans	95,923	138,740	72,405
Originated Portfolio [Member] | Land development [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	0	0	0
Financing receivable, recorded investment 61 to 89 days past due	0	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	0	0	0
Financing receivable, recorded investment, Nonaccrual loans	290	225	2,267
Financing receivable recorded investment, Total past due	290	225	2,267
Financing receivable, recorded investment, current	3,972	4,303	5,499
Financing receivable, recorded investment, Total loans	4,262	4,528	7,766
Originated Portfolio [Member] | Real estate residential [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	1,246	2,126	1,259
Financing receivable, recorded investment 61 to 89 days past due	88	54	1,138
Financing receivable, recorded investment accruing loans past due 90 days or more	172	557	0
Financing receivable, recorded investment, Nonaccrual loans	6,514	6,706	6,589
Financing receivable recorded investment, Total past due	8,020	9,443	8,986
Financing receivable, recorded investment, current	999,552	988,558	941,815
Financing receivable, recorded investment, Total loans	1,007,572	998,001	950,801
Originated Portfolio [Member] | Consumer installment [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	2,143	3,620	1,950
Financing receivable, recorded investment 61 to 89 days past due	344	512	313
Financing receivable, recorded investment accruing loans past due 90 days or more	0	0	0
Financing receivable, recorded investment, Nonaccrual loans	433	500	806
Financing receivable recorded investment, Total past due	2,920	4,632	3,069
Financing receivable, recorded investment, current	832,439	814,746	670,721
Financing receivable, recorded investment, Total loans	835,359	819,378	673,790
Originated Portfolio [Member] | Home equity [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	1,728	3,039	1,500
Financing receivable, recorded investment 61 to 89 days past due	197	660	256
Financing receivable, recorded investment accruing loans past due 90 days or more	429	1,346	622
Financing receivable, recorded investment, Nonaccrual loans	1,870	1,667	2,046
Financing receivable recorded investment, Total past due	4,224	6,712	4,424
Financing receivable, recorded investment, current	564,067	562,384	495,440
Financing receivable, recorded investment, Total loans	568,291	569,096	499,864
Acquired Portfolio [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	2,299	2,994	98
Financing receivable, recorded investment 61 to 89 days past due	378	461	0
Financing receivable, recorded investment accruing loans past due 90 days or more	11,231	19,892	11,523
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	13,908	23,347	11,621
Financing receivable, recorded investment, current	640,304	674,816	277,203
Financing receivable, recorded investment, Total loans	654,212	698,163	288,824
Acquired Portfolio [Member] | Commercial [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	59	133	0
Financing receivable, recorded investment 61 to 89 days past due	5	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	2,089	5,427	6,496
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	2,153	5,560	6,496
Financing receivable, recorded investment, current	89,109	93,423	71,024
Financing receivable, recorded investment, Total loans	91,262	98,983	77,520
Acquired Portfolio [Member] | Real estate commercial [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	1,784	2,014	0
Financing receivable, recorded investment 61 to 89 days past due	138	352	0
Financing receivable, recorded investment accruing loans past due 90 days or more	6,271	11,052	2,549
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	8,193	13,418	2,549
Financing receivable, recorded investment, current	336,382	339,804	147,900
Financing receivable, recorded investment, Total loans	344,575	353,222	150,449
Acquired Portfolio [Member] | Real estate construction [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	0	0	0
Financing receivable, recorded investment 61 to 89 days past due	0	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	0	0	0
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	0	0	0
Financing receivable, recorded investment, current	0	14,005	12,679
Financing receivable, recorded investment, Total loans	0	14,005	12,679
Acquired Portfolio [Member] | Land development [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	0	0	0
Financing receivable, recorded investment 61 to 89 days past due	0	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	1,537	1,653	2,089
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	1,537	1,653	2,089
Financing receivable, recorded investment, current	7,117	12,569	3,906
Financing receivable, recorded investment, Total loans	8,654	14,222	5,995
Acquired Portfolio [Member] | Real estate residential [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	104	156	0
Financing receivable, recorded investment 61 to 89 days past due	0	0	0
Financing receivable, recorded investment accruing loans past due 90 days or more	868	18	58
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	972	174	58
Financing receivable, recorded investment, current	108,901	112,215	11,150
Financing receivable, recorded investment, Total loans	109,873	112,389	11,208
Acquired Portfolio [Member] | Consumer installment [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	3	55	49
Financing receivable, recorded investment 61 to 89 days past due	1	3	0
Financing receivable, recorded investment accruing loans past due 90 days or more	11	454	0
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	15	512	49
Financing receivable, recorded investment, current	8,692	9,680	1,573
Financing receivable, recorded investment, Total loans	8,707	10,192	1,622
Acquired Portfolio [Member] | Home equity [Member]
Schedule representing the aging status of the recorded investment in loans by classes
Financing receivable, recorded investment 31 to 60 days past due	349	636	49
Financing receivable, recorded investment 61 to 89 days past due	234	106	0
Financing receivable, recorded investment accruing loans past due 90 days or more	455	1,288	331
Financing receivable, recorded investment, Nonaccrual loans	0	0	0
Financing receivable recorded investment, Total past due	1,038	2,030	380
Financing receivable, recorded investment, current	90,103	93,120	28,971
Financing receivable, recorded investment, Total loans	$ 91,141	$ 95,150	$ 29,351