Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities
Net loss	$ (73,023)	$ (29,756)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	6,366	6,123
Stock-based compensation	19,792	14,472
Amortization of debt discount and issuance costs	4,674	1,128
Non-cash lease expense	4,727	0
Other	(401)	0
Change in assets and liabilities:
Accrued revenue	(9,071)	80
Inventory	(82,766)	(21,779)
Prepaid expenses and other assets	(82)	1,808
Accounts payable	579	702
Accrued liabilities and other payables	18,994	11,357
Operating lease liabilities	(5,207)	0
Deferred rent	112	(913)
Origination of loans held for sale	(285,182)	(56,157)
Proceeds from sale of loans originated as held for sale	267,850	52,127
Net cash used in operating activities	(132,638)	(20,808)
Investing activities
Purchases of property and equipment	(12,821)	(5,528)
Purchases of investments	(106,063)	0
Sales of investments	1,005	0
Maturities of investments	4,900	0
Net cash used in investing activities	(112,979)	(5,528)
Financing activities
Proceeds from the issuance of shares resulting from employee equity plans	10,869	17,314
Tax payments related to net share settlements on restricted stock units	(2,856)	(705)
Borrowings from warehouse credit facilities	280,129	54,806
Repayments of warehouse credit facilities	(262,875)	(51,031)
Other payables - deposits held in escrow	637	7,684
Proceeds from issuance of convertible notes, net of issuance costs	0	138,953
Proceeds from follow on offering	0	107,593
Cash paid for debt issuance costs	(152)	0
Net cash provided by financing activities	25,752	274,614
Effect of exchange rate changes on cash and cash equivalents	28	0
Net change in cash, cash equivalents, and restricted cash	(219,837)	248,278
Cash, cash equivalents, and restricted cash:
Beginning of period	439,055	212,658
End of period	219,218	460,936
Supplemental disclosure of cash flow information
Cash paid for interest	2,460	0
Non-cash transactions
Stock-based compensation capitalized in property and equipment	(931)	(363)
Property and equipment additions in accounts payable and accrued liabilities	(404)	(25)
Leasehold improvements paid directly by lessor	$ (4,298)	$ (926)