Fair Value Measurements - Significant Unobservable Inputs (Details) - Nonrecurring $ in Thousands	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Level III \| Measurement Input, Default Rate \| Discounted cash flow
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Loans impaired, measurement input	0.00
Level III \| Measurement Input, Temporary Reduction In Payment \| Discounted cash flow \| Minimum
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	0.17	0.07
Level III \| Measurement Input, Temporary Reduction In Payment \| Discounted cash flow \| Maximum
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	(0.70)	(0.70)
Level III \| Measurement Input, Temporary Reduction In Payment \| Discounted cash flow \| Weighted Average
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	(0.35)	(0.06)
Level III \| Measurement Input, Appraised Value \| Appraisal of collateral
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Other real estate owned, measurement input percentage	(0.20)	(0.20)
Level III \| Measurement Input, Appraised Value \| Appraisal of collateral \| Minimum
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	0.00	0.00
Level III \| Measurement Input, Appraised Value \| Appraisal of collateral \| Maximum
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	(0.40)	(0.90)
Level III \| Measurement Input, Appraised Value \| Appraisal of collateral \| Weighted Average
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Impaired loans, measurement input percentage	(0.06)	(0.20)
Other real estate owned, measurement input percentage	(0.20)	(0.20)
Impaired loans
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	$ 17,879	$ 18,704
Impaired loans \| Level III
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	17,879	18,704
Impaired loans \| Level III \| Discounted cash flow
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	11,607	12,929
Impaired loans \| Level III \| Appraisal of collateral
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	6,272	5,775
Other real estate owned
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	325	402
Other real estate owned \| Level III
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	325	402
Other real estate owned \| Level III \| Appraisal of collateral
Listing of significant unobservable inputs used in the fair value measurement process for items valued utilizing level III techniques
Total assets, fair value	$ 325	$ 402

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- Definition

Loans Impaired, Measurement Input

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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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

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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