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Loans and Allowance for Loan Losses - Related Party Loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) director
Loans and Leases Receivable, Related Parties [Roll Forward]
Balance at beginning of year	$ 11,852	$ 1,988
Additions	863	3,186
Advances	0	74
Repayments	(2,080)	(128)
Reclassified due to a change in borrower status	0	6,732
Balance at end of year	10,635	$ 11,852
Directors, Officers, Principal Shareholders and Associates
Related Party Transaction [Line Items]
Number of new board of directors | director		2
Undisbursed commitment to related parties	$ 9,100	$ 9,100

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- Definition

Loans and Leases Receivable, Reclassified as Unrelated-party Loan

+ References

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- Definition

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
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- Definition

Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Unused amount of commitments to extend credit to customers.

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