Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 1,241,255	$ 925,276
Restricted cash	101,790	20,544
Short-term investments	140,843	131,561
Accounts receivable, net of allowances for credit losses of $182 and $160	47,416	54,719
Inventory	97,371	49,158
Loans held for sale	43,447	42,539
Prepaid expenses	15,224	12,131
Other current assets	7,014	4,898
Total current assets	1,694,360	1,240,826
Property and equipment, net	47,649	43,988
Right-of-use assets, net	47,932	44,149
Long-term investments	6,906	11,922
Goodwill and intangibles, net	10,894	11,016
Other assets, noncurrent	8,836	8,619
Total assets	1,816,577	1,360,520
Current liabilities
Accounts payable	15,568	5,644
Accrued liabilities	75,754	69,460
Other payables	19,117	13,184
Warehouse Agreement Borrowings	40,663	39,029
Secured revolving credit facility	48,851	23,949
Convertible senior notes, net	23,428	22,482
Lease liabilities	12,611	11,973
Total current liabilities	235,992	185,721
Lease liabilities and deposits, noncurrent	53,333	49,339
Convertible senior notes, net, noncurrent	1,136,974	488,268
Payroll tax liabilities, noncurrent	6,812	6,812
Total liabilities	1,433,111	730,140
Commitments and contingencies (Note 7)
Series A convertible preferred stock—par value $0.001 per share; 10,000,000 shares authorized; 40,000 shares issued and outstanding	39,834	39,823
Stockholders’ equity
Common stock—par value $0.001 per share; 500,000,000 shares authorized; 103,983,585 and 103,000,594 shares issued and outstanding, respectively	104	103
Additional paid-in capital	641,702	860,556
Accumulated other comprehensive income	161	211
Accumulated deficit	(298,335)	(270,313)
Total stockholders’ equity	343,632	590,557
Total liabilities, mezzanine equity and stockholders’ equity	$ 1,816,577	$ 1,360,520