Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net income	$ 32,692	$ 10,102
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Change in fair value of financial instruments	18,356	901
Stock-based compensation	25,050	8,622
Loss (gain) on loan servicing arrangement, net	(8,705)	67
Depreciation and amortization	2,781	816
Non-cash interest expense	776	18
Net changes in operating assets and liabilities:
Purchase of loans for immediate resale	(3,014,594)	(1,294,634)
Proceeds from immediate resale of loans	3,014,594	1,294,634
Purchase of loans held-for-sale	(443,190)	(18,240)
Principal payments received for loans held-for-sale	20,328	2,637
Proceeds from sale of loans held-for-sale	50,764	38,140
Other assets	7,287	(9,988)
Operating lease liability and right-of-use asset	2,584	234
Accounts payable	3,371	(5,807)
Payable to investors	32,204	10,989
Accrued expenses and other liabilities	(11,093)	4,601
Net cash provided by (used in) operating activities	(266,795)	43,092
Cash flows from investing activities
Proceeds from sale of loans held-for-investment	0	8,329
Principal payments received for loans held-for-investment	9,397	3,002
Principal payments received for notes receivable and repayments of residual certificates	2,067	3,119
Purchase of loans held-for-investment	0	(12,947)
Purchase of non-marketable equity security	(1,000)	0
Purchase of property and equipment	(1,629)	(267)
Capitalized software costs	(3,658)	(334)
Net cash provided by investing activities	5,177	902
Cash flows from financing activities
Proceeds from borrowings	80,004	5,831
Repayments of borrowings	(6,990)	(26,584)
Proceeds from issuance of common stock under employee stock purchase plan	4,431	0
Proceeds from exercise of stock options	5,626	1,492
Net cash provided by (used in) financing activities	83,071	(19,261)
Net increase (decrease) in cash and restricted cash	(178,547)	24,733
Cash and restricted cash
Cash and restricted cash at beginning of period	1,191,241	311,333
Cash and restricted cash at end of period	1,012,694	336,066
Supplemental disclosures of cash flow information
Cash paid for interest	1,763	1,030
Cash paid for income taxes	18	0
Supplemental disclosures of non-cash investing and financing activities
Capitalized stock-based compensation expense	1,627	122
Reclassification of loans held-for-investment to held-for-sale	$ 109,792	$ 26