Fair Value - Assets and Liabilities Recorded at Fair Value on a Nonrecurring Basis (Details) - Impaired loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets with fair value adjustments on a nonrecurring basis
Total impairment losses	$ 700	$ 700	$ 400
Fair Value Measurements, Nonrecurring \| Level 3
Assets with fair value adjustments on a nonrecurring basis
Fair value	$ 402	$ 87

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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
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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.

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