Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net income (loss)	$ 23,635	$ 24,635	$ (14,880)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Provision for credit losses	173,369	148,541	152,926
Depreciation and amortization	6,433	7,802	9,951
Amortization of debt issuance costs	3,605	6,656	3,806
Stock-based compensation	10,964	11,819	12,515
Amortization of net deferred origination costs	66,955	58,121	48,755
Changes in servicing rights, at fair value	69	290	2,097
Gain on sales of loans	0	0	2,485
Unfunded loan commitment reserve	1,308	1,438	535
Gain on extinguishment of debt	0	0	312
Gain on lease termination	0	(1,481)	0
Loss on disposal of fixed assets	3,199	5,737	0
Amortization of intangibles	501	0	0
Changes in operating assets and liabilities:
Other assets	(15,059)	(4,972)	4,768
Accounts payable	2,476	1,535	(2,597)
Interest payable	(51)	119	208
Accrued expenses and other liabilities	4,992	5,595	(4,852)
Originations of loans held for sale	0	0	49,813
Capitalized net deferred origination costs of loans held for sale	0	0	1,667
Proceeds from sale of loans held for sale	0	0	51,463
Principal repayments of loans held for sale	0	0	1,135
Net cash provided by operating activities	282,396	265,835	211,553
Cash flows from investing activities
Purchases of property, equipment and software	(3,189)	(1,058)	(1,340)
Capitalized internal-use software	(9,265)	(5,385)	(2,919)
Originations of loans and finance receivables, excluding rollovers into new originations	(2,079,442)	(2,115,800)	(1,758,600)
Proceeds from sale of loans held for investment	0	0
Proceeds from sale of loans held for investment			24,826
Payments of net deferred origination costs	(69,426)	(66,682)	(46,133)
Principal repayments of loans and finance receivables	1,860,723	1,788,031	1,639,117
Purchase of loans	0	(801)	(13,840)
Acquisition of shares in business combination	(3,015)	0	0
Net cash used in investing activities	(303,614)	(401,695)	(158,889)
Cash flows from financing activities
Investments by noncontrolling interests	0	3,400	3,443
Tax withholding related to vesting of restricted stock units	(1,959)	(1,857)	(1,268)
Repurchases of common stock	(43,985)	0	0
Proceeds from exercise of stock options	98	78	454
Purchase of interest rate cap	0	1,725	0
Issuance of common stock under employee stock purchase plan	2,228	1,435	1,838
Proceeds from the issuance of debt	761,424	759,171	211,781
Payments of debt issuance costs	(5,338)	(6,034)	(4,108)
Repayments of debt principal	(691,555)	(632,744)	(273,679)
Distribution to noncontrolling interest	0	0	957
Net cash (used in) provided by financing activities	20,913	121,724	(62,496)
Effect of exchange rate changes on cash and cash equivalents	(465)	(3,050)	670
Net increase (decrease) in cash, cash equivalents and restricted cash	(770)	(17,186)	(9,162)
Cash and cash equivalents at beginning of period	97,638	114,824	123,986
Cash, cash equivalents, and restricted cash at end of period	96,868	97,638	114,824
Reconciliation to amounts on consolidated balance sheets
Total cash, cash equivalents and restricted cash	96,868	97,638	114,824
Supplemental disclosure of other cash flow information
Cash paid for interest	40,004	42,208	41,918
Cash paid for taxes	9,315	0	0
Supplemental disclosures of non-cash investing and financing activities
Stock-based compensation included in capitalized internal-use software	270	243	175
Unpaid principal balance of term loans rolled into new originations	395,192	$ 368,385	$ 306,250
Additional lease liabilities incurred during the respective year	4,576
Additional right-of-use assets incurred during the respective year	$ 4,136