Loans (Summary of Recorded Investment of Commercial Loans by Risk Rating Categories) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	$ 4,308,209	$ 4,250,117	$ 3,081,931
Commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,922,259	1,905,879	1,356,169
Real estate commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	2,143,051	2,112,162	1,616,923
Real estate construction [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	242,899	232,076	108,839
Originated Portfolio [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	3,263,902	3,130,721	2,637,440
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	3,073,067	2,942,826	2,447,891
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	88,502	65,943	85,985
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	56,664	67,714	58,941
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	43,999	52,143	44,617
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	1,670	2,095	6
Originated Portfolio [Member] | Commercial [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,563,924	1,521,515	1,264,907
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	1,466,094	1,418,301	1,176,021
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	43,129	34,727	40,999
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	35,437	39,933	28,983
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	17,595	26,459	18,904
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	1,669	2,095	0
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	1,500,310	1,424,059	1,272,348
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	1,409,991	1,341,202	1,175,373
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	44,210	31,036	44,248
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	20,250	26,658	27,961
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	25,858	25,163	24,760
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	1	0	6
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	199,668	185,147	100,185
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	196,982	183,323	96,497
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	1,163	180	738
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	977	1,123	1,997
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	546	521	953
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
Acquired Portfolio [Member]
Recorded investment of loans in commercial loan portfolio by risk rating categories
Recorded investment (loan balance), Commercial, Total	1,044,307	1,119,396	444,491
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	949,083	1,011,895	396,259
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	45,209	54,803	19,338
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	43,055	43,119	19,384
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	6,960	9,579	9,510
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	358,335	384,364	91,262
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	319,672	340,782	71,422
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	25,978	28,321	11,299
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	11,103	11,607	6,509
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	1,582	3,654	2,032
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	642,741	688,103	344,575
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	590,151	629,430	318,113
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	17,692	23,926	7,786
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	30,679	29,975	12,735
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	4,219	4,772	5,941
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	43,231	46,929	8,654
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	39,260	41,683	6,724
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	1,539	2,556	253
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	1,273	1,537	140
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	1,159	1,153	1,537
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