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Purchased Receivables - Summary of Allowance for Loan Losses Purchased Receivables (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at beginning of year | $ 200 | $ 171 | $ 181
Balance at end of year | 190 | 200 | 171
Purchased Receivable |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Reserve for (recovery from) purchased receivables | $ (10) | $ 29 | $ (10)

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- Definition Reserve For Purchased Receivable Gains Losses + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration

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- Definition Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.5) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130534-203044 + Details
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Balance Type: | debit
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- Details
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Balance Type: |
Period Type: |