Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income	$ 26,028	$ 24,468	$ 51,730	$ 48,304
Provision for loan losses	100	450	100	750
Net interest income after provision for loan losses	25,928	24,018	51,630	47,554
Noninterest income	15,261	12,814	29,281	32,184
Depreciation and amortization expense	988	945	2,026	1,892
Other noninterest expenses related to segments	23,311	21,503	45,804	49,848
Total noninterest expense	24,299	22,448	47,830	51,740
Income before income taxes	16,890	14,384	33,081	27,998
Income tax expense	5,387	4,587	10,568	8,903
Net income	11,503	9,797	22,513	19,095
Total assets	3,644,477	3,317,022	3,644,477	3,317,022	$ 3,586,874
Expenditures for long-lived assets	1,118	1,390	2,344	2,681
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	21,212	19,799	41,837	39,538
Provision for loan losses	100	450	100	750
Net interest income after provision for loan losses	21,112	19,349	41,737	38,788
Noninterest income	5,588	3,860	10,666	8,401
Depreciation and amortization expense	638	621	1,310	1,206
Other noninterest expenses related to segments	13,868	13,219	27,454	26,772
Total noninterest expense	14,506	13,840	28,764	27,978
Income before income taxes	12,194	9,369	23,639	19,211
Income tax expense	3,993	3,102	7,723	6,363
Net income	8,201	6,267	15,916	12,848
Total assets	3,058,410	2,704,109	3,058,410	2,704,109
Expenditures for long-lived assets	943	1,308	2,010	2,383
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income	(9)	(7)	(23)	(11)
Provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	(9)	(7)	(23)	(11)
Noninterest income	8,912	8,530	17,347	16,595
Depreciation and amortization expense	299	272	605	583
Other noninterest expenses related to segments	6,465	5,482	12,380	10,869
Total noninterest expense	6,764	5,754	12,985	11,452
Income before income taxes	2,139	2,769	4,339	5,132
Income tax expense	838	1,018	1,682	1,894
Net income	1,301	1,751	2,657	3,238
Total assets	53,236	53,303	53,236	53,303
Expenditures for long-lived assets	87	65	201	236
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income	4,825	4,676	9,916	8,777
Provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	4,825	4,676	9,916	8,777
Noninterest income	761	424	1,268	7,188
Depreciation and amortization expense	51	52	111	103
Other noninterest expenses related to segments	2,978	2,802	5,970	12,207
Total noninterest expense	3,029	2,854	6,081	12,310
Income before income taxes	2,557	2,246	5,103	3,655
Income tax expense	556	467	1,163	646
Net income	2,001	1,779	3,940	3,009
Total assets	532,831	559,610	532,831	559,610
Expenditures for long-lived assets	$ 88	$ 17	$ 133	$ 62