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Investment Securities Investment Securities Text Tags (Details) | 3 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Jun. 30, 2018 USD ($)
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 27 | 35 |
Available-for-sale | $ 78,391,000 | $ 79,845,000 |
Percentage Available-for-sale Securities | 87.80% |  |
Held-to-maturity | $ 10,892,000 | 11,137,000 |
Percentage Held-to-maturity Securities | 12.20% |  |
Trading | $ 0 |  |
Proceeds from Sale of Available-for-sale Securities | $ 0 |  |
Mortgage-backed securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 43.70% |  |
Number of AFS securities in Unrealized Loss Positions, greater than or equal to 12 months | 17 |  |
Held-to-maturity | $ 9,892,000 | 10,137,000 |
US Government Agency Securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 50.90% |  |
Number of AFS securities in Unrealized Loss Positions, greater than or equal to 12 months | 2 |  |
Corporate Bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Number of AFS securities in Unrealized Loss Positions, greater than or equal to 12 months | 3 |  |
Held-to-maturity | $ 1,000,000 | $ 1,000,000 |
Accounting Standards Update 2016-01 |  |  |
Schedule of Investments [Line Items] |  |  |
Cumulative Effect of New Accounting Principle |  |  | $ 0
Accounting Standards Update 2016-01 | Accumulated Deficit |  |  |
Schedule of Investments [Line Items] |  |  |
Cumulative Effect of New Accounting Principle |  |  | $ (721,000)

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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