Purchased Receivables - Summary of Allowance for Loan Losses Purchased Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	$ 190	$ 200	$ 171
Balance at end of year	94	190	200
Purchased Receivable
Allowance for Loan and Lease Losses [Roll Forward]
Reserve for (recovery from) purchased receivables	$ (96)	$ (10)	$ 29

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-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=116634182&loc=SL114868664-224227

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration