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Premises, Equipment, and Leases (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Property, Plant and Equipment [Abstract] |  |
Maximum duration of noncancelable operating leases, time period | 30 years |
Impairment losses | $ 6.0 | $ 5.0
Gain/(loss) on sale of properties, before applicable income taxes | $ 0.4 | $ 1.8

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- Definition Maximum Duration Of Noncancelable Operating Leases For Premises and Equipment + References No definition available. + Details
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- Definition This element represents the amount of gain (loss) on sale of properties during the reporting period gross of the applicable income taxes realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 974 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-15.(a)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6875705&loc=d3e641549-123027 + Details
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- Definition Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- References No definition available. + Details
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