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Revenue from Contracts with Customers Revenue from Contracts with Customers (Schedule of Disaggregation of Revenue) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | $ 505,867 | $ 524,703 | $ 501,341
Revenue from Contracts with Customers In Scope of ASC 606 [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 451,796 | 483,891 | 467,304
Revenue from Contracts with Customers In Scope of ASC 606 [Member] | Bank Card Transaction Fees [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 151,797 | 167,879 | 171,576
Revenue from Contracts with Customers In Scope of ASC 606 [Member] | Trust Fees [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 160,637 | 155,628 | 147,964
Revenue from Contracts with Customers In Scope of ASC 606 [Member] | Deposit Account Charges and Other Fees [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 93,227 | 95,983 | 94,517
Revenue from Contracts with Customers In Scope of ASC 606 [Member] | Consumer Brokerage Services [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 15,095 | 15,804 | 15,807
Revenue from Contracts with Customers In Scope of ASC 606 [Member] | Other Non-Interest Income [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | 31,040 | 48,597 | 37,440
Revenue Not In Scope of ASC 606 [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Non-interest income | $ 54,071 | $ 40,812 | $ 34,037

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- Definition The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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