Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income	$ 25,702	$ 23,836
Provision for loan losses	0	300
Net interest income after provision for loan losses	25,702	23,536
Noninterest income	14,020	19,370
Depreciation and amortization expense	1,037	947
Other noninterest expenses related to segments	22,494	28,345
Total noninterest expense	23,531	29,292
Income before income taxes	16,191	13,614
Income tax expense	5,181	4,316
Net income	11,010	9,298
Total assets	3,602,514	3,194,146	3,586,874
Expenditures for long-lived assets	1,226	1,291
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	20,625	19,739
Provision for loan losses	0	300
Net interest income after provision for loan losses	20,625	19,439
Noninterest income	5,078	4,541
Depreciation and amortization expense	671	585
Other noninterest expenses related to segments	13,587	13,553
Total noninterest expense	14,258	14,138
Income before income taxes	11,445	9,842
Income tax expense	3,730	3,261
Net income	7,715	6,581
Total assets	3,015,691	2,577,350
Expenditures for long-lived assets	1,067	1,075
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income	(14)	(4)
Provision for loan losses	0	0
Net interest income after provision for loan losses	(14)	(4)
Noninterest income	8,435	8,065
Depreciation and amortization expense	306	311
Other noninterest expenses related to segments	5,915	5,387
Total noninterest expense	6,221	5,698
Income before income taxes	2,200	2,363
Income tax expense	844	876
Net income	1,356	1,487
Total assets	52,568	52,475
Expenditures for long-lived assets	114	171
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income	5,091	4,101
Provision for loan losses	0	0
Net interest income after provision for loan losses	5,091	4,101
Noninterest income	507	6,764
Depreciation and amortization expense	60	51
Other noninterest expenses related to segments	2,992	9,405
Total noninterest expense	3,052	9,456
Income before income taxes	2,546	1,409
Income tax expense	607	179
Net income	1,939	1,230
Total assets	534,255	564,321
Expenditures for long-lived assets	$ 45	$ 45