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Concentrations of Credit Risk (Details) - Credit concentration risk $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) customer | Dec. 31, 2016 USD ($)
U.S. Government, its agencies and Government Sponsored Enterprises (GSEs) |  |
Concentration Risk [Line Items] |  |
Concentration risk amount | $ | $ 358.4 | $ 299.5
Concentration risk percentage | 74.00% | 72.00%
Loans portfolio |  |
Concentration Risk [Line Items] |  |
Number of major borrowers | customer | 0 |
Concentration risk, threshold for major borrower, percentage | 2.00% |
Loans on real estate |  |
Concentration Risk [Line Items] |  |
Concentration risk percentage | 81.00% | 79.00%

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- Definition Concentration Risk, Percentage, Threshold For Major Borrower + References No definition available. + Details
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- Definition Number Of Major Borrowers + References No definition available. + Details
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- Definition Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
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