LOANS RECEIVABLE AND REVENUE - Allowance For Doubtful Accounts - CSO Guarantee Liability (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	$ 87,363	$ 56,246
Charge-offs	(162,531)	(87,884)
Recoveries	65,411	61,187
Net charge-offs	(97,120)	(26,697)
Provision for losses	81,031	61,736
Effect of foreign currency translation	24	101
Balance, end of period	71,298	91,386
Consumer Portfolio Segment | Single-Pay
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	5,916	5,699
Charge-offs	(47,707)	(46,706)
Recoveries	35,009	33,886
Net charge-offs	(12,698)	(12,820)
Provision for losses	11,302	11,798
Effect of foreign currency translation	(35)	58
Balance, end of period	4,485	4,735
Consumer Portfolio Segment | Unsecured Installment
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	60,827	33,483
Charge-offs	(81,096)	(27,647)
Recoveries	16,943	15,797
Net charge-offs	(64,153)	(11,850)
Provision for losses	51,033	38,851
Effect of foreign currency translation	95	38
Balance, end of period	47,802	60,522
Consumer Portfolio Segment | Secured Installment
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	14,194	11,885
Charge-offs	(12,704)	(3,163)
Recoveries	4,035	5,399
Net charge-offs	(8,669)	2,236
Provision for losses	6,640	7,435
Effect of foreign currency translation	0	1
Balance, end of period	12,165	21,557
Consumer Portfolio Segment | Open-End
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	6,426	5,179
Charge-offs	(20,349)	(9,229)
Recoveries	9,377	5,353
Net charge-offs	(10,972)	(3,876)
Provision for losses	11,428	3,265
Effect of foreign currency translation	(36)	4
Balance, end of period	6,846	4,572
Consumer Portfolio Segment | Other
Financing Receivable, Allowance for Credit Losses And Guarantor Obligations [Roll Forward]
Balance, beginning of period	0	0
Charge-offs	(675)	(1,139)
Recoveries	47	752
Net charge-offs	(628)	(387)
Provision for losses	628	387
Effect of foreign currency translation	0	0
Balance, end of period	$ 0	$ 0