Fair Value - Fair Value on Recurring Basis - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 46,874	$ 52,287
Percentage of portfolio in residential mortgage backed securities	58.00%
Available-for-sale securities	$ 46,874
Residential mortgage backed securities guaranteed by Government National Mortgage Association or Federal National Mortgage Association or Federal Home Loan Mortgage Corporation	26,900
Equity securities	1,200	1,206
Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 27,325	$ 31,878

Percentage Of Portfolio In Residential Mortgage Backed Securities

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- Definition

Residential Mortgage Backed Securities Guaranteed By Government National Mortgage Association Or Federal National Mortgage Association Or Federal Home Loan Mortgage Corporation

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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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 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: 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=82897076&loc=d3e27161-111563

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value of investments in trading equity securities and other forms of trading securities that provide ownership interests.

+ References

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