Disaggregated Revenue and Deferred Revenue - Schedule of Other Income by Component (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Borrower late fee income	$ 3,196	$ 3,253	$ 9,870	$ 8,994
Gain on investments and notes receivable, net of losses	1,948	2,503	5,779	10,291
Other	5,458	7,978	14,808	16,681
Other income	13,439	16,673	38,658	44,808
Management fees
Disaggregation of Revenue [Line Items]
Revenue	2,084	1,756	6,007	4,673
Investment advisory services
Disaggregation of Revenue [Line Items]
Revenue	$ 753	$ 1,183	$ 2,194	$ 4,169

Other Income, Miscellaneous

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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.

+ References

No definition available.

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All amounts that are due to the servicer of a financial asset as a result of the debt holder not meeting the monthly payment terms.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

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Amount of unrealized and realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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Amount of revenue and income classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.4)
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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