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Fair Value Of Assets And Liabilities (Schedule Of Unobservable Inputs Utilized In Determining The Fair Value Of Level 3 Recurring And Non-Recurring Measurements) (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Dec. 31, 2017 | Jun. 30, 2017
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Securities available-for-sale |  |  |  | $ 5,170,255 |  |
Loans held-for-sale (elected fair value) |  | $ 18,940 |  | 20,881 |  |
Loans, net of unearned income |  | 27,701,740 | [1] | 27,658,929 | [1] | $ 19,989,319
OREO | [2] | 29,712 |  | 43,382 |  |
Residential Real Estate |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
OREO |  | 6,100 |  | 6,300 |  |
Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Securities available-for-sale |  | 4,724,411 |  | 4,931,402 |  |
Loans held-for-sale (elected fair value) |  | 18,940 |  | 20,881 |  |
Derivative liabilities, other |  | 135,349 |  | 85,061 |  |
Other assets |  | 189,259 |  | 121,456 |  |
Non Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans, net of unearned income |  | 29,061 |  | 26,666 |  |
OREO |  | 26,457 |  | 39,566 |  |
Other assets |  | 24,699 |  | 26,521 |  |
Non Recurring | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans held-for-sale (elected fair value) |  | 607 |  | 618 |  |
Derivative liabilities, other | Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Derivative liabilities, other |  | 9,432 |  | 5,684 |  |
Other assets |  | 163 |  |  |  |
Level 3 | Residential Real Estate |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans held-for-sale (elected fair value) |  | 17,325 |  | 19,544 |  |
Level 3 | Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Securities available-for-sale |  | 5,787 |  | 1,270 |  |
Loans held-for-sale (elected fair value) |  | 16,718 |  | 18,926 |  |
Derivative liabilities, other |  | 9,425 |  | 5,645 |  |
Other assets |  | 0 |  | 0 |  |
Level 3 | Non Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans, net of unearned income |  | 29,061 |  | 26,666 |  |
OREO |  | 26,457 |  | 39,566 |  |
Other assets |  | 24,699 |  | 26,521 |  |
Level 3 | Non Recurring | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans held-for-sale (elected fair value) |  | 607 |  | 618 |  |
Level 3 | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Derivative liabilities, other |  | 9,425 |  | 5,645 |  |
Level 3 | Derivative liabilities, other | Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Derivative liabilities, other |  | 9,425 |  | 5,645 |  |
Other assets |  | 0 |  |  |  |
Level 3 | Loans held-for-sale- unguaranteed interest in SBA loans |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loans held-for-sale (elected fair value) |  | 1,025 |  | 1,473 |  |
Level 3 | Other assets | Non Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Other assets |  | 24,699 |  | 26,521 |  |
Level 3 | Discounted cash flow | Minimum | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Visa covered litigation resolution amount |  | $ 5,000,000 |  | $ 4,400,000 |  |
Level 3 | Discounted cash flow | Minimum | Values Utilized | Loans held-for-sale- unguaranteed interest in SBA loans |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Bond equivalent yield |  | 13.00% |  | 9.00% |  |
Level 3 | Discounted cash flow | Minimum | 2% - 11% Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 2.00% |  |  |  |
Level 3 | Discounted cash flow | Minimum | 5% - 12% Values Utilized | Loans held- for-sale | Residential Real Estate | HELOC |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 5.00% |  | 5.00% |  |
Level 3 | Discounted cash flow | Minimum | 50% - 70% Percent Values Utilized | Loans held- for-sale | Residential Real Estate |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Foreclosure losses |  | 50.00% |  | 50.00% |  |
Level 3 | Discounted cash flow | Minimum | 5% - 25% Of Unpaid Principle Balance | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  | 5.00% |  |  |  |
Level 3 | Discounted cash flow | Minimum | Percent Of Unpaid Principle Balance | Loans held- for-sale | Residential Real Estate | HELOC |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  | 50.00% |  | 15.00% |  |
Level 3 | Discounted cash flow | Minimum | 8% - 12% Values Utilized | Loans held-for-sale- unguaranteed interest in SBA loans |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 8.00% |  | 8.00% |  |
Level 3 | Discounted cash flow | Minimum | 20% - 30% Values Utilized | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Probability of resolution scenarios |  | 20.00% |  |  |  |
Level 3 | Discounted cash flow | Minimum | 10% - 30% Values Utilized | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Probability of resolution scenarios |  |  |  | 10.00% |  |
Level 3 | Discounted cash flow | Minimum | 24 - 48 Months | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Time until resolution |  | 24 months |  |  |  |
Level 3 | Discounted cash flow | Minimum | 18 to 48 months | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Time until resolution |  |  |  | 18 months |  |
Level 3 | Discounted cash flow | Minimum | 0% - 15% Adjustment To Yield | Other assets |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Adjustments to current sales yields for specific properties |  | 0.00% |  | 0.00% |  |
Level 3 | Discounted cash flow | Minimum | 2% - 12% Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  |  |  | 2.00% |  |
Level 3 | Discounted cash flow | Minimum | 5% - 30% Percent Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  |  |  | 5.00% |  |
Level 3 | Discounted cash flow | Maximum | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Visa covered litigation resolution amount |  | $ 5,600,000 |  | $ 5,200,000 |  |
Level 3 | Discounted cash flow | Maximum | Values Utilized | Loans held-for-sale- unguaranteed interest in SBA loans |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Bond equivalent yield |  | 14.00% |  | 10.00% |  |
Level 3 | Discounted cash flow | Maximum | 2% - 11% Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 11.00% |  |  |  |
Level 3 | Discounted cash flow | Maximum | 5% - 12% Values Utilized | Loans held- for-sale | Residential Real Estate | HELOC |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 12.00% |  | 12.00% |  |
Level 3 | Discounted cash flow | Maximum | 50% - 70% Percent Values Utilized | Loans held- for-sale | Residential Real Estate |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Foreclosure losses |  | 70.00% |  | 70.00% |  |
Level 3 | Discounted cash flow | Maximum | 5% - 25% Of Unpaid Principle Balance | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  | 25.00% |  |  |  |
Level 3 | Discounted cash flow | Maximum | Percent Of Unpaid Principle Balance | Loans held- for-sale | Residential Real Estate | HELOC |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  | 100.00% |  | 100.00% |  |
Level 3 | Discounted cash flow | Maximum | 8% - 12% Values Utilized | Loans held-for-sale- unguaranteed interest in SBA loans |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 12.00% |  | 12.00% |  |
Level 3 | Discounted cash flow | Maximum | 20% - 30% Values Utilized | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Probability of resolution scenarios |  | 30.00% |  |  |  |
Level 3 | Discounted cash flow | Maximum | 10% - 30% Values Utilized | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Probability of resolution scenarios |  |  |  | 30.00% |  |
Level 3 | Discounted cash flow | Maximum | 24 - 48 Months | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Time until resolution |  | 48 months |  |  |  |
Level 3 | Discounted cash flow | Maximum | 18 to 48 months | Derivative liabilities, other | Derivative liabilities, other |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Time until resolution |  |  |  | 48 months |  |
Level 3 | Discounted cash flow | Maximum | 0% - 15% Adjustment To Yield | Other assets |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Adjustments to current sales yields for specific properties |  | 15.00% |  | 15.00% |  |
Level 3 | Discounted cash flow | Maximum | 2% - 12% Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  |  |  | 12.00% |  |
Level 3 | Discounted cash flow | Maximum | 5% - 30% Percent Values Utilized | Loans held- for-sale | Residential Real Estate | Loans held-for-sale—first mortgages |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Loss severity trends - First mortgage |  |  |  | 30.00% |  |
Level 3 | Appraisals from comparable properties | Minimum | 0% -10% Of Appraisal | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Marketability adjustments for specific properties |  | 0.00% |  | 0.00% |  |
Level 3 | Appraisals from comparable properties | Minimum | 0% -10% Of Appraisal | OREO |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Adjustment for value changes since appraisal |  | 0.00% |  | 0.00% |  |
Level 3 | Appraisals from comparable properties | Minimum | 0% - 25% Of Appraisal | Other assets |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Marketability adjustments for specific properties |  | 0.00% |  | 0.00% |  |
Level 3 | Appraisals from comparable properties | Maximum | 0% -10% Of Appraisal | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Marketability adjustments for specific properties |  | 10.00% |  | 10.00% |  |
Level 3 | Appraisals from comparable properties | Maximum | 0% -10% Of Appraisal | OREO |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Adjustment for value changes since appraisal |  | 10.00% |  | 10.00% |  |
Level 3 | Appraisals from comparable properties | Maximum | 0% - 25% Of Appraisal | Other assets |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Marketability adjustments for specific properties |  | 25.00% |  | 25.00% |  |
Level 3 | Other collateral valuations | Minimum | 20% - 50% Of Gross Value | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Borrowing base certificates adjustment |  | 20.00% |  | 20.00% |  |
Level 3 | Other collateral valuations | Minimum | 0% - 25% Of Reported Value | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Financial Statements/Auction values adjustment |  | 0.00% |  | 0.00% |  |
Level 3 | Other collateral valuations | Maximum | 20% - 50% Of Gross Value | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Borrowing base certificates adjustment |  | 50.00% |  | 50.00% |  |
Level 3 | Other collateral valuations | Maximum | 0% - 25% Of Reported Value | Loans, net of unearned income |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Financial Statements/Auction values adjustment |  | 25.00% |  | 25.00% |  |
Level 3 | Interest- only strips- AFS | Recurring |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Securities available-for-sale |  | $ 5,787 |  | $ 1,270 |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  | 11.00% |  |  |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | 17% Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Bond equivalent yield |  |  |  | 17.00% |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | Minimum | 12% - 14% Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Bond equivalent yield |  | 12.00% |  |  |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | Minimum | 10% - 11% Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  |  |  | 10.00% |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | Maximum | 12% - 14% Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Bond equivalent yield |  | 14.00% |  |  |  |
Level 3 | Interest- only strips- AFS | Discounted cash flow | Maximum | 10% - 11% Values Utilized | Available-for-sale securities |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |
Constant prepayment rate |  |  |  | 11.00% |  |
[1] | June 30, 2018 and December 31, 2017 include $21.4 million and $22.7 million, respectively, of held-to-maturity consumer mortgage loans secured by residential real estate in process of foreclosure.
[2] | June 30, 2018 and December 31, 2017 include $6.1 million and $6.3 million, respectively, of foreclosed residential real estate.

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 + Details
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- Definition Loss, including interest and principal, incurred on a defaulted security, expressed as a percentage of the original principal balance, used as an input to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details
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