Summary of Significant Accounting Policies - Originated Loans and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Originated Loans and Allowance for Loan Losses
Non-accrual Status Collection Days Past Due	90 days
Loans classified as TDRs	$ 5,450	$ 10,900
Performing \| Maximum
Originated Loans and Allowance for Loan Losses
Threshold for classification as performing loans	90 days
Nonperforming \| Minimum
Originated Loans and Allowance for Loan Losses
Threshold for classification as performing loans	90 days

Period of time past contractual due date after which loans are generally placed on non-accrual status.

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- Definition

Period of time past due which is used as a threshold for classification of loans as performing or non-performing.

+ References

No definition available.

+ 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.

+ Details

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- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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