Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating Activities
Net loss	$ (66,728)	$ (79,804)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	6,865	3,809
Stock-based compensation	14,416	12,282
Amortization of debt discount and issuance costs	3,477	3,031
Non-cash lease expense	4,522	2,943
Impairment costs	1,420	0
Other	(1,190)	(100)
Change in assets and liabilities:
Accounts receivable, net	(14,959)	(23,323)
Inventory	65,153	(62,960)
Prepaid expenses and other assets	5,446	1,230
Accounts payable	1,040	1,350
Accrued liabilities, other payables, and non-current payroll tax liabilities	14,244	26,489
Lease liabilities	(5,481)	(3,301)
Origination of loans held for sale	(294,076)	(153,335)
Proceeds from sale of loans originated as held for sale	274,595	128,080
Net cash provided by (used in) operating activities	8,744	(143,609)
Investing activities
Purchases of property and equipment	(6,072)	(9,504)
Purchases of investments	(88,724)	(70,312)
Sales of investments	3,183	100
Maturities of investments	40,351	0
Net cash used in investing activities	(51,262)	(79,716)
Financing activities
Proceeds from the issuance of common stock, net of issuance costs	69,701	0
Proceeds from the issuance of shares resulting from employee equity plans	11,052	8,965
Tax payments related to net share settlements on restricted stock units	(6,065)	(1,792)
Borrowings from warehouse credit facilities	290,891	149,900
Repayments to warehouse credit facilities	(271,627)	(125,206)
Borrowings from secured revolving credit facility	39,587	0
Repayments to secured revolving credit facility	(36,816)	0
Other payables—deposits held in escrow	19,056	11,602
Principal payments for finance lease obligations	(30)	0
Cash paid for debt issuance costs	(4)	0
Net cash provided by financing activities	155,546	43,469
Effect of exchange rate changes on cash and cash equivalents	(22)	38
Net change in cash, cash equivalents, and restricted cash	113,006	(179,818)
Cash, cash equivalents, and restricted cash:
Beginning of period	247,448	439,055
End of period	360,454	259,237
Supplemental disclosure of cash flow information
Cash paid for interest	2,133	1,202
Non-cash transactions
Stock-based compensation capitalized in property and equipment	1,151	561
Property and equipment additions in accounts payable and accrued liabilities	1,492	620
Leasehold improvements paid directly by lessor	0	3,444
ProceedsFromIssuanceOfTemporaryEquity	$ 39,801	$ 0