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Goodwill and Core Deposit Intangibles - Intangible Assets Narrative (Details) - Core Deposits Intangibles - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, useful life (in years) | 10 years |
Proceeds from sale of custodial rights | $ 6.2 |
Reductions due to sale of accounts | $ 0.0 | $ (3.2)

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- Definition Finite-Lived Intangible Assets, Increase (Decrease) From Sale Of Accounts + References No definition available. + Details
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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The cash inflow from disposal of asset without physical form usually arising from contractual or other legal rights, excluding goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details
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- Details
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