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Allowance for Credit Losses and Allowance for Unfunded Commitments and Letters of Credit (Narrative) (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease) | $ 38,100,000 |
Minimum loan balance of nonaccrual, collateral dependent loans considered for ACL | 500,000 |
Provision for credit losses | $ 41,500,000 | $ 1,362,000

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- Definition Minimum loan balance of nonaccrual, collateral dependent loans considered for ACL + References No definition available. + Details
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- Definition Amount of increase (decrease) in allowance for credit loss on financing receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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- Definition Amount of expense related to estimated loss from loan and lease transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 + Details
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