Loans and Allowance for Loan Losses (Schedule Of Impaired Loans) (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	$ 21,611,000		$ 21,611,000		$ 11,022,000
Recorded Investment, With allowance recorded	167,414,000		167,414,000		189,264,000
Recorded Investment	189,025,000		189,025,000		200,286,000
Unpaid Principal Balance, With no related allowance recorded	32,545,000		32,545,000		14,259,000
Unpaid Principal Balance, With allowance recorded	169,434,000		169,434,000		189,498,000
Unpaid Principal Balance	201,979,000		201,979,000		203,757,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	14,933,000		14,933,000		14,908,000
Related Allowance	14,933,000		14,933,000		14,908,000
Average Recorded Investment, With no related allowance recorded	16,079,000		13,901,000		32,314,000
Average Recorded Investment, With allowance recorded	178,152,000		182,280,000		190,695,000
Average Recorded Investment	194,231,000	$ 232,500,000	196,181,000	$ 233,800,000	223,009,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	1,349,000		2,781,000		6,961,000
Interest Income Recognized	1,349,000	$ 0	2,781,000	$ 0	6,961,000
Total commercial and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	21,549,000		21,549,000		8,220,000
Recorded Investment, With allowance recorded	85,995,000		85,995,000		103,114,000
Recorded Investment	107,544,000		107,544,000		111,334,000
Unpaid Principal Balance, With no related allowance recorded	32,458,000		32,458,000		9,576,000
Unpaid Principal Balance, With allowance recorded	86,269,000		86,269,000		103,292,000
Unpaid Principal Balance	118,727,000		118,727,000		112,868,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	9,473,000		9,473,000		9,515,000
Related Allowance	9,473,000		9,473,000		9,515,000
Average Recorded Investment, With no related allowance recorded	13,575,000		11,129,000		28,351,000
Average Recorded Investment, With allowance recorded	96,362,000		100,637,000		90,966,000
Average Recorded Investment	109,937,000		111,766,000		119,317,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	528,000		1,158,000		2,992,000
Interest Income Recognized	528,000		1,158,000		2,992,000
Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	21,549,000		21,549,000		8,220,000
Recorded Investment, With allowance recorded	45,171,000		45,171,000		65,715,000
Recorded Investment	66,720,000		66,720,000		73,935,000
Unpaid Principal Balance, With no related allowance recorded	32,458,000		32,458,000		9,576,000
Unpaid Principal Balance, With allowance recorded	45,385,000		45,385,000		65,851,000
Unpaid Principal Balance	77,843,000		77,843,000		75,427,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	6,813,000		6,813,000		7,406,000
Related Allowance	6,813,000		6,813,000		7,406,000
Average Recorded Investment, With no related allowance recorded	13,575,000		11,129,000		21,686,000
Average Recorded Investment, With allowance recorded	57,930,000		62,564,000		50,468,000
Average Recorded Investment	71,505,000		73,693,000		72,154,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	155,000		428,000		1,610,000
Interest Income Recognized	155,000		428,000		1,610,000
Total commercial and industrial | Owner-occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	40,824,000		40,824,000		37,399,000
Recorded Investment	40,824,000		40,824,000		37,399,000
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	40,884,000		40,884,000		37,441,000
Unpaid Principal Balance	40,884,000		40,884,000		37,441,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	2,660,000		2,660,000		2,109,000
Related Allowance	2,660,000		2,660,000		2,109,000
Average Recorded Investment, With no related allowance recorded	0		0		6,665,000
Average Recorded Investment, With allowance recorded	38,432,000		38,073,000		40,498,000
Average Recorded Investment	38,432,000		38,073,000		47,163,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	373,000		730,000		1,382,000
Interest Income Recognized	373,000		730,000		1,382,000
Total commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		56,000
Recorded Investment, With allowance recorded	53,805,000		53,805,000		56,840,000
Recorded Investment	53,805,000		53,805,000		56,896,000
Unpaid Principal Balance, With no related allowance recorded	0		0		1,740,000
Unpaid Principal Balance, With allowance recorded	55,545,000		55,545,000		56,896,000
Unpaid Principal Balance	55,545,000		55,545,000		58,636,000
Related Allowance, With no related allowance recorded	0		0
Related Allowance, With allowance recorded	4,688,000		4,688,000		4,240,000
Related Allowance	4,688,000		4,688,000		4,240,000
Average Recorded Investment, With no related allowance recorded	0		19,000		2,262,000
Average Recorded Investment, With allowance recorded	54,084,000		53,350,000		68,344,000
Average Recorded Investment	54,084,000		53,369,000		70,606,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	520,000		1,010,000		2,473,000
Interest Income Recognized	520,000		1,010,000		2,473,000
Total commercial real estate | Investment properties
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	24,218,000		24,218,000		23,364,000
Recorded Investment	24,218,000		24,218,000		23,364,000
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	24,218,000		24,218,000		23,364,000
Unpaid Principal Balance	24,218,000		24,218,000		23,364,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	1,659,000		1,659,000		1,100,000
Related Allowance	1,659,000		1,659,000		1,100,000
Average Recorded Investment, With no related allowance recorded	0		0		123,000
Average Recorded Investment, With allowance recorded	24,439,000		23,604,000		28,749,000
Average Recorded Investment	24,439,000		23,604,000		28,872,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	220,000		418,000		1,144,000
Interest Income Recognized	220,000		418,000		1,144,000
Total commercial real estate | 1-4 family properties
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	10,458,000		10,458,000		15,056,000
Recorded Investment	10,458,000		10,458,000		15,056,000
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	10,458,000		10,458,000		15,056,000
Unpaid Principal Balance	10,458,000		10,458,000		15,056,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	309,000		309,000		504,000
Related Allowance	309,000		309,000		504,000
Average Recorded Investment, With no related allowance recorded	0		0		323,000
Average Recorded Investment, With allowance recorded	11,217,000		11,466,000		16,257,000
Average Recorded Investment	11,217,000		11,466,000		16,580,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	226,000		442,000		925,000
Interest Income Recognized	226,000		442,000		925,000
Total commercial real estate | Land and development
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		56,000
Recorded Investment, With allowance recorded	19,129,000		19,129,000		18,420,000
Recorded Investment	19,129,000		19,129,000		18,476,000
Unpaid Principal Balance, With no related allowance recorded	0		0		1,740,000
Unpaid Principal Balance, With allowance recorded	20,869,000		20,869,000		18,476,000
Unpaid Principal Balance	20,869,000		20,869,000		20,216,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	2,720,000		2,720,000		2,636,000
Related Allowance	2,720,000		2,720,000		2,636,000
Average Recorded Investment, With no related allowance recorded	0		19,000		1,816,000
Average Recorded Investment, With allowance recorded	18,428,000		18,280,000		23,338,000
Average Recorded Investment	18,428,000		18,299,000		25,154,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	74,000		150,000		404,000
Interest Income Recognized	74,000		150,000		404,000
Total consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	62,000		62,000		2,746,000
Recorded Investment, With allowance recorded	27,614,000		27,614,000		29,310,000
Recorded Investment	27,676,000		27,676,000		32,056,000
Unpaid Principal Balance, With no related allowance recorded	87,000		87,000		2,943,000
Unpaid Principal Balance, With allowance recorded	27,620,000		27,620,000		29,310,000
Unpaid Principal Balance	27,707,000		27,707,000		32,253,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	772,000		772,000		1,153,000
Related Allowance	772,000		772,000		1,153,000
Average Recorded Investment, With no related allowance recorded	2,504,000		2,753,000		1,701,000
Average Recorded Investment, With allowance recorded	27,706,000		28,293,000		31,385,000
Average Recorded Investment	30,210,000		31,046,000		33,086,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	301,000		613,000		1,496,000
Interest Income Recognized	301,000		613,000		1,496,000
Total consumer | Home equity lines
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		2,746,000
Recorded Investment, With allowance recorded	3,915,000		3,915,000		5,096,000
Recorded Investment	3,915,000		3,915,000		7,842,000
Unpaid Principal Balance, With no related allowance recorded	0		0		2,943,000
Unpaid Principal Balance, With allowance recorded	3,915,000		3,915,000		5,096,000
Unpaid Principal Balance	3,915,000		3,915,000		8,039,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	174,000		174,000		114,000
Related Allowance	174,000		174,000		114,000
Average Recorded Investment, With no related allowance recorded	724,000		1,423,000		1,205,000
Average Recorded Investment, With allowance recorded	3,262,000		3,822,000		7,476,000
Average Recorded Investment	3,986,000		5,245,000		8,681,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	30,000		76,000		334,000
Interest Income Recognized	30,000		76,000		334,000
Total consumer | Consumer mortgages
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	62,000		62,000		0
Recorded Investment, With allowance recorded	18,767,000		18,767,000		18,668,000
Recorded Investment	18,829,000		18,829,000		18,668,000
Unpaid Principal Balance, With no related allowance recorded	87,000		87,000		0
Unpaid Principal Balance, With allowance recorded	18,767,000		18,767,000		18,668,000
Unpaid Principal Balance	18,854,000		18,854,000		18,668,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	350,000		350,000		569,000
Related Allowance	350,000		350,000		569,000
Average Recorded Investment, With no related allowance recorded	1,780,000		1,330,000		496,000
Average Recorded Investment, With allowance recorded	19,459,000		19,283,000		19,144,000
Average Recorded Investment	21,239,000		20,613,000		19,640,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	199,000		394,000		896,000
Interest Income Recognized	199,000		394,000		896,000
Total consumer | Credit cards
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	0		0		0
Recorded Investment	0		0		0
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	0		0		0
Related Allowance	0		0		0
Average Recorded Investment, With no related allowance recorded	0		0		0
Average Recorded Investment, With allowance recorded	4,985,000		0		0
Average Recorded Investment	4,985,000		0		0
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	0		0		0
Interest Income Recognized	0		0		0
Total consumer | Other consumer loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	4,932,000		4,932,000		5,546,000
Recorded Investment	4,932,000		4,932,000		5,546,000
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	4,938,000		4,938,000		5,546,000
Unpaid Principal Balance	4,938,000		4,938,000		5,546,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	248,000		248,000		470,000
Related Allowance	248,000		248,000		470,000
Average Recorded Investment, With no related allowance recorded	0		0		0
Average Recorded Investment, With allowance recorded	0		5,188,000		4,765,000
Average Recorded Investment	0		5,188,000		4,765,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	72,000		143,000		266,000
Interest Income Recognized	$ 72,000		$ 143,000		$ 266,000