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Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | $ 16,230,056 | $ 14,627,638
30 – 89 Days Past Due |  | 50,855 | 80,100
90 Days Past Due and Still Accruing |  | 22,190 | 19,859
Non-accrual |  | 26,540 | 10,220
Total | [1] | 16,329,641 | 14,737,817
Business [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 6,546,087 | 5,565,449
Real Estate - Construction And Land [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 1,021,595 | 899,377
Real Estate - Business [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 3,026,117 | 2,833,554
Real Estate - Personal [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 2,820,030 | 2,354,760
Consumer [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 1,950,502 | 1,964,145
Revolving Home Equity [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 307,083 | 349,251
Consumer Credit Card [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 655,078 | 764,977
Overdrafts [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Total |  | 3,149 | 6,304
Commercial Portfolio Segment [Member] | Business [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 6,517,838 | 5,545,104
30 – 89 Days Past Due |  | 2,252 | 12,064
90 Days Past Due and Still Accruing |  | 3,473 | 792
Non-accrual |  | 22,524 | 7,489
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 1,021,592 | 882,826
30 – 89 Days Past Due |  | 0 | 13,046
90 Days Past Due and Still Accruing |  | 3 | 3,503
Non-accrual |  | 0 | 2
Commercial Portfolio Segment [Member] | Real Estate - Business [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 3,016,215 | 2,830,494
30 – 89 Days Past Due |  | 7,666 | 2,030
90 Days Past Due and Still Accruing |  | 6 | 0
Non-accrual |  | 2,230 | 1,030
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 2,808,886 | 2,345,243
30 – 89 Days Past Due |  | 6,521 | 6,129
90 Days Past Due and Still Accruing |  | 2,837 | 1,689
Non-accrual |  | 1,786 | 1,699
Personal Banking Portfolio Segment [Member] | Consumer [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 1,921,822 | 1,928,082
30 – 89 Days Past Due |  | 25,417 | 34,053
90 Days Past Due and Still Accruing |  | 3,263 | 2,010
Non-accrual |  | 0 | 0
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 305,037 | 347,258
30 – 89 Days Past Due |  | 1,656 | 1,743
90 Days Past Due and Still Accruing |  | 390 | 250
Non-accrual |  | 0 | 0
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 635,770 | 742,659
30 – 89 Days Past Due |  | 7,090 | 10,703
90 Days Past Due and Still Accruing |  | 12,218 | 11,615
Non-accrual |  | 0 | 0
Personal Banking Portfolio Segment [Member] | Overdrafts [Member] |  |  |
Loans And Allowance For Loan Losses [Line Items] |  |  |
Current or Less than 30 days Past Due |  | 2,896 | 5,972
30 – 89 Days Past Due |  | 253 | 332
90 Days Past Due and Still Accruing |  | 0 | 0
Non-accrual |  | $ 0 | $ 0
[1] | (1) Accrued interest receivable totaled $41.9 million at December 31, 2020 and was included within other assets on the consolidated balance sheet. For the year ended December 31, 2020, the Company wrote-off accrued interest by reversing interest income of $329 thousand and $5.7 million in the Commercial and Personal Banking portfolios, respectively.

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