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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Total of TDR loans charged-off within previous 12 months	$ 0	$ 0
Consumer loans | Installment and other consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts Modified | contract	2	1
Pre-Modification Outstanding Recorded Investment	$ 254,000	$ 50,000
Post-Modification Outstanding Recorded Investment	245,000	50,000
Post-Modification Outstanding Recorded Investment at Period End	$ 172,000	$ 47,000

X

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings at end of period.

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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