Purchased Receivables - Allowance on Net Purchase Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward]
Balance, beginning of period			$ 200
Charge-offs	$ (100)	$ (207)	(1,204)	$ (486)
Balance, end of period	201		201
Purchased Receivable
Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward]
Balance, beginning of period	209	183	200	171
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Charge-offs net of recoveries	0	0	0	0
Reserve for purchased receivables	(8)	11	1	23
Balance, end of period	$ 201	$ 194	$ 201	$ 194

Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward]

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- Definition

Reserve For Purchased Receivable Gains Losses

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the allowance for doubtful accounts.

+ References

No definition available.

+ Details

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- Definition

Amount of recoveries of receivables doubtful of collection that were previously charged off.

+ References

No definition available.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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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

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