Loans And Allowance For Credit Losses (Summary Of Selected Information On TDRs That Includes Recorded Investment On An Accruing And Nonaccruing Basis By Loan Class And Modification Type) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
Current Fiscal Year End Date		--12-31
Loans Receivable, Gross, Commercial and Industrial		$ 14,003	$ 13,452
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		5	3
Loans and Leases Receivable, Gross, Consumer, Construction		597	486
Loans and Leases Receivable, Gross, Consumer, Mortgage		6,662	5,891
Loans and Leases Receivable, Gross, Consumer, Home Equity		2,777	2,645
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		509	481
Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		139	151
Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		226	251
Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		4	0
Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		47	47
Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		62	60
Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		1	1
Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		23	22
Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		10	17
Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	1
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		14,003	13,452
Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		70	69
Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		73	78
Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2	8
Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	2
Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		14	17
Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5	8
Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		16	25
Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5	10
Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		15	14
Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	2
One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		36	42
One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		8	8
Construction And Other Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	2
Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2	1
Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	2
Consumer Other Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		597	486
Loans and Leases Receivable, Gross, Consumer, Mortgage		6,662	5,891
Loans and Leases Receivable, Gross, Consumer, Home Equity		2,777	2,645
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		509	481
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		5	1
Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	2
Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		53	57
Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		9	12
Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		1	0
Accruing [Member] | Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		1	0
Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	0
Accruing [Member] | Construction And Other Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	0
Accruing [Member] | Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		1	0
Accruing [Member] | Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	0
Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		4	3
Nonaccruing [Member] | Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		3	0
Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		1	1
Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	2
Nonaccruing [Member] | Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		4	1
Nonaccruing [Member] | Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0	2
Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		87	100
Multiple Modification Types [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		86	86
Multiple Modification Types [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		123	132
Multiple Modification Types [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		47	38
Multiple Modification Types [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		29	37
Multiple Modification Types [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		9	14
Multiple Modification Types [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	3
Multiple Modification Types [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		37	46
Multiple Modification Types [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		30	34
Multiple Modification Types [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5	6
Multiple Modification Types [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		33	28
Multiple Modification Types [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			10
Multiple Modification Types [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		14
Multiple Modification Types [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2
Multiple Modification Types [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			10
Multiple Modification Types [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		7
Multiple Modification Types [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			4
Multiple Modification Types [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		3	3
Multiple Modification Types [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		26	30
Multiple Modification Types [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		1	1
Multiple Modification Types [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		24	25
Multiple Modification Types [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			12
Multiple Modification Types [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5
Multiple Modification Types [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Multiple Modification Types [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Multiple Modification Types [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Multiple Modification Types [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			3
Multiple Modification Types [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3
Multiple Modification Types [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Multiple Modification Types [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	1
Multiple Modification Types [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		5	5
Multiple Modification Types [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	22	12
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	52	51
Other Recorded Investment Resulting From Following Modification [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	19	8
Other Recorded Investment Resulting From Following Modification [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	29	34
Other Recorded Investment Resulting From Following Modification [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	0	2
Other Recorded Investment Resulting From Following Modification [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	0	4
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	30	39
Other Recorded Investment Resulting From Following Modification [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	3	2
Other Recorded Investment Resulting From Following Modification [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	[1]	1	1
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		12	0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			8
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		7
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			2
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		1	0
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		2	2
Other Recorded Investment Resulting From Following Modification [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		28	33
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			2
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			2
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		1	1
Other Recorded Investment Resulting From Following Modification [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Payment Deferral [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2	1
Payment Deferral [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5	7
Payment Deferral [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Payment Deferral [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	4
Payment Deferral [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	1
Payment Deferral [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Payment Deferral [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	6
Payment Deferral [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	0
Payment Deferral [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	2
Payment Deferral [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		0	0
Payment Deferral [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Payment Deferral [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Payment Deferral [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Payment Deferral [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Payment Deferral [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Payment Deferral [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Payment Deferral [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Payment Deferral [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		1	0
Payment Deferral [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Payment Deferral [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		2	1
Payment Deferral [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			3
Payment Deferral [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Payment Deferral [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Payment Deferral [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Payment Deferral [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Payment Deferral [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Payment Deferral [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Payment Deferral [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Payment Deferral [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Payment Deferral [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		0	0
Payment Deferral [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	2
Principal Forgiveness [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		15	17
Principal Forgiveness [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		23	20
Principal Forgiveness [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	1
Principal Forgiveness [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		5	0
Principal Forgiveness [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Principal Forgiveness [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Principal Forgiveness [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		8	3
Principal Forgiveness [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		15	16
Principal Forgiveness [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	3
Principal Forgiveness [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		0	0
Principal Forgiveness [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Principal Forgiveness [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		9	10
Principal Forgiveness [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		6	6
Principal Forgiveness [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Principal Forgiveness [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		5	0
Principal Forgiveness [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Principal Forgiveness [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Principal Forgiveness [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		1	1
Principal Forgiveness [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		2	2
Principal Forgiveness [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Maturity Or Team Extension [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		6	25
Maturity Or Team Extension [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		12	28
Maturity Or Team Extension [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	19
Maturity Or Team Extension [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		6	2
Maturity Or Team Extension [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	4
Maturity Or Team Extension [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	1
Maturity Or Team Extension [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		6	3
Maturity Or Team Extension [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	2
Maturity Or Team Extension [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Maturity Or Team Extension [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		2	19
Maturity Or Team Extension [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Maturity Or Team Extension [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Maturity Or Team Extension [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Maturity Or Team Extension [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Maturity Or Team Extension [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Maturity Or Team Extension [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			4
Maturity Or Team Extension [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		2	1
Maturity Or Team Extension [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		0	1
Maturity Or Team Extension [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		1	0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		3	0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		0	0
Maturity Or Team Extension [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Interest Rate Below Market [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		8	10
Interest Rate Below Market [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		11	13
Interest Rate Below Market [Member] | Commercial Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	3
Interest Rate Below Market [Member] | Commercial Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	1
Interest Rate Below Market [Member] | Commercial Real Estate Portfolio Segment [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		6	4
Interest Rate Below Market [Member] | Commercial Real Estate Portfolio Segment [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2	2
Interest Rate Below Market [Member] | Nonaccruing Trouble Debt Restructuring [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		3	3
Interest Rate Below Market [Member] | Consumer Loan [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1	3
Interest Rate Below Market [Member] | Consumer Loan [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0	0
Interest Rate Below Market [Member] | Accruing [Member] | Commercial And Industrial [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		0	0
Interest Rate Below Market [Member] | Accruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			3
Interest Rate Below Market [Member] | Accruing [Member] | Owner Occupied [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Interest Rate Below Market [Member] | Accruing [Member] | Construction And Land Development [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Interest Rate Below Market [Member] | Accruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			4
Interest Rate Below Market [Member] | Accruing [Member] | Term [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		6
Interest Rate Below Market [Member] | Accruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Interest Rate Below Market [Member] | Accruing [Member] | Home Equity Line of Credit [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Interest Rate Below Market [Member] | Accruing [Member] | One Through Four Family Residential [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		1	3
Interest Rate Below Market [Member] | Accruing [Member] | Construction And Other Consumer Real Estate [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		0	0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Commercial And Industrial [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans Receivable, Gross, Commercial and Industrial		0	1
Interest Rate Below Market [Member] | Nonaccruing [Member] | Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Owner Occupied [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		1
Interest Rate Below Market [Member] | Nonaccruing [Member] | Municipal [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Municipal [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Construction And Land Development [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Term [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			2
Interest Rate Below Market [Member] | Nonaccruing [Member] | Term [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment		2
Interest Rate Below Market [Member] | Nonaccruing [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Home Equity Line of Credit [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity		0	0
Interest Rate Below Market [Member] | Nonaccruing [Member] | One Through Four Family Residential [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage		0	0
Interest Rate Below Market [Member] | Nonaccruing [Member] | Construction And Other Consumer Real Estate [Member] | Nonaccruing [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Gross, Consumer, Construction		$ 0	$ 0

[1] Includes TDRs that resulted from other modification types including, but not limited to, a legal judgment awarded on different terms, a bankruptcy plan confirmed on different terms, a settlement that includes the delivery of collateral in exchange for debt reduction, etc.2 Includes TDRs that resulted from a combination of any of the previous modification types.