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Fair Value - Assets Measured at Fair Value on a Non-Recurring Basis (Details)	3 Months Ended
	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			$ 1,000
Other Real Estate Owned Write Downs	$ 0	$ 25,000
Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			1,000
Nonrecurring [Member] | Nonresidential real estate loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired Loan Fair Value			243,000
Nonrecurring [Member] | Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			1,000
Nonrecurring [Member] | Other Investments [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments, Fair Value Disclosure			3,427,000
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Nonresidential real estate loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired Loan Fair Value			0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other Investments [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments, Fair Value Disclosure			0
Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member] | Nonresidential real estate loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired Loan Fair Value			0
Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member] | Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			0
Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member] | Other Investments [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments, Fair Value Disclosure			0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Nonresidential real estate loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired Loan Fair Value			243,000
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Other real estate owned			1,000
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Investments [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments, Fair Value Disclosure			$ 3,427,000
Sales Comparison Valuation Technique [Member] | Land Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Real estate owned, measurement input	0.123
Measurement Input, Comparability Adjustment [Member] | Maximum [Member] | Real Estate Properties [Domain] | Nonresidential Real Estate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Real estate owned, measurement input			0.1522
Measurement Input, Comparability Adjustment [Member] | Minimum [Member] | Real Estate Properties [Domain] | Nonresidential Real Estate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Real estate owned, measurement input			(0.0366)
Measurement Input, Comparability Adjustment [Member] | Weighted Average [Member] | Real Estate Properties [Domain] | Nonresidential Real Estate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Real estate owned, measurement input			0.1100

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- Definition

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+ References

No definition available.

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- Definition

Real estate acquired through foreclosure fair value.

+ References

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+ References

No definition available.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of gain recognized in the income statement for an increase in valuation of real estate owned (REO).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 35
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=29634951&loc=d3e1720-110224

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