Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015		Sep. 30, 2014	Sep. 30, 2015		Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income (expense)	$ 25,997		$ 24,938	$ 77,727		$ 73,242
Provision for loan losses	200		600	300		1,350
Net interest income after provision for loan losses	25,797		24,338	77,427		71,892
Noninterest income	13,913		13,125	43,194		45,309
Depreciation and amortization expense	1,080		947	3,106		2,839
Other noninterest expenses related to segments	23,458		21,100	69,262		70,948
Total noninterest expense	24,538		22,047	72,368		73,787
Income before income taxes	15,172		15,416	48,253		43,414
Income tax expense	4,964		4,878	15,532		13,781
Net income	10,208		10,538	32,721		29,633
Total assets	3,674,836		3,415,882	3,674,836		3,415,882	$ 3,586,874
Expenditures for long-lived assets	1,118		634	3,220		3,315
Acquisition related expenses	504		0	937		0
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	21,278		19,965	63,115		59,503
Provision for loan losses	200		600	300		1,350
Net interest income after provision for loan losses	21,078		19,365	62,815		58,153
Noninterest income	4,498		4,370	15,164		12,771
Depreciation and amortization expense	626		627	1,936		1,833
Other noninterest expenses related to segments	13,805		12,793	41,259		39,565
Total noninterest expense	14,431		13,420	43,195		41,398
Income before income taxes	11,145		10,315	34,784		29,526
Income tax expense	3,747		3,401	10,878		9,764
Net income	7,398		6,914	23,906		19,762
Total assets	3,074,611		2,792,759	3,074,611		2,792,759
Expenditures for long-lived assets	1,006		327	2,774		2,710
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	(15)		(8)	(38)		(19)
Provision for loan losses	0		0	0		0
Net interest income after provision for loan losses	(15)		(8)	(38)		(19)
Noninterest income	8,902		8,374	26,249		24,969
Depreciation and amortization expense	404		269	1,009		852
Other noninterest expenses related to segments	6,820	[1]	5,620	19,200	[2]	16,489
Total noninterest expense	7,224		5,889	20,209		17,341
Income before income taxes	1,663		2,477	6,002		7,609
Income tax expense	688		942	2,682		2,836
Net income	975		1,535	3,320		4,773
Total assets	62,461		51,012	62,461		51,012
Expenditures for long-lived assets	51		241	252		477
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	4,734		4,981	14,650		13,758
Provision for loan losses	0		0	0		0
Net interest income after provision for loan losses	4,734		4,981	14,650		13,758
Noninterest income	513		381	1,781		7,569
Depreciation and amortization expense	50		51	161		154
Other noninterest expenses related to segments	2,833		2,687	8,803		14,894
Total noninterest expense	2,883		2,738	8,964		15,048
Income before income taxes	2,364		2,624	7,467		6,279
Income tax expense	529		535	1,972		1,181
Net income	1,835		2,089	5,495		5,098
Total assets	537,764		572,111	537,764		572,111
Expenditures for long-lived assets	$ 61		$ 66	$ 194		$ 128

[1] Other noninterest expenses for the Wealth Management Services segment includes $504 thousand of acquisition related expenses for the three months ended September 30, 2015. See Note 3 for additional information.

[2] Other noninterest expenses for the Wealth Management Services segment includes $937 thousand of acquisition related expenses for the nine months ended September 30, 2015. See Note 3 for additional information.