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Basis of Presentation (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2018 USD ($) | Sep. 30, 2018 item | Dec. 31, 2017 USD ($)
Basis of presentation |  |  |
Number of operating segments | item |  | 1 |
Number of active operating bank subsidiaries | item |  | 5 |
On-time reclassification from AOCI to retained earnings, relating to the Tax Cuts and Jobs Act of 2017 | $ | $ 5,979,000 |  |
Equity securities |  |  |
Basis of presentation |  |  |
Net unrealized loss on available-for-sale equity securities | $ |  |  | $ 189,000

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- Definition Represents the number of active operating subsidiaries of the entity. + References No definition available. + Details
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- Definition Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017. + References No definition available. + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details
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