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Basis of Presentation (Details) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2018 USD ($) | Jun. 30, 2018 item | Dec. 31, 2017 USD ($)
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 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 Amount of unrealized gain (loss) on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + 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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