Fair Value - Valuation Methodology and Unobservable Inputs (Details) - Non-Recurring Basis - Significant Unobservable Inputs (Level 3) - item	Dec. 31, 2018	Dec. 31, 2017
Impaired loans carried at fair value of collateral
Fair Value
Valuation Technique(s)	gaap:MeasurementInputAppraisedValueMember	us-gaap:MeasurementInputAppraisedValueMember
Unobservable Input(s)	gaap:MarketApproachValuationTechniqueMember	us-gaap:MarketApproachValuationTechniqueMember
Impaired loans carried at fair value of collateral \| Minimum
Fair Value
Adjustment for differences between the comparable sales (as a percent)	(0.03)	(0.16)
Impaired loans carried at fair value of collateral \| Maximum
Fair Value
Adjustment for differences between the comparable sales (as a percent)	(0.01)	0.07
Impaired loans carried at fair value of collateral \| Weighted Average
Fair Value
Adjustment for differences between the comparable sales (as a percent)	(0.0283)	(0.04)
Real estate owned \| Church
Fair Value
Adjustment for differences between the comparable sales (as a percent)	(0.11)	(0.06)
Valuation Technique(s)	gaap:MeasurementInputAppraisedValueMember	us-gaap:MeasurementInputAppraisedValueMember
Unobservable Input(s)	gaap:MarketApproachValuationTechniqueMember	us-gaap:MarketApproachValuationTechniqueMember
Real estate owned \| Church \| Weighted Average
Fair Value
Adjustment for differences between the comparable sales (as a percent)	(0.1085)	(0.06)

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

Indicates measurement input for 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Indicates valuation technique for measuring investment in debt security 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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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