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Stockholders' Equity and Regulatory Capital (Narrative Disclosures) (Details) - right |  | 12 Months Ended
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Jul. 15, 2008 | Dec. 31, 2017
Regulatory Capital Requirements [Abstract] |  |
Dividend Paid of One Common Share Purchase Right for Each Outstanding Share of Common Stock | 1 |
Description of possible effects of noncompliance or less than adequately capitalized |  | Failure to meet minimum capital requirements can result in certain mandatory, and possibly additional discretionary actions on the part of regulators, that if undertaken, could have a direct material effect on the Bank’s assets, liabilities and certain off-balance-sheet items as calculated under regulatory practices.

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- Definition Dividend Paid of One Common Share Purchase Right for Each Outstanding Share of Common Stock + References No definition available. + Details
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- Definition Description of the possible material effects of noncompliance with capital adequacy requirements when the entity is not in compliance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details
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