Finance Receivables, net (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Changes in estimated recoveries	$ 19,801	$ 0	$ 6,985	$ 0
Face value of receivable portfolios		1,800,000		6,600,000
Payments to acquire finance receivables		289,200		608,000
Estimated remaining collections on purchased receivables		513,000		1,020,000
Unamortized purchased principal (purchase price) under the cost recovery method		$ 39,400		$ 39,400
Financing Receivable, Allowance For Credit Loss, Changes In Expected Future Recoveries	(99,698)		(120,324)
Financing Receivable, Allowance For Credit Loss, Recoveries In Excess (Shortfall) Of Forecast	$ 119,499		$ 127,309
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivables Assumptions, Changes In Timing Of Collections, Period			6 months
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivables Assumptions, Changes In Timing Of Collections, Period			18 months