CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (21,045)	$ (7,611)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Provision for transaction losses	1,606	1,038
Depreciation and amortization	4,786	2,827
Amortization of debt issuance costs	26	26
Amortization of discount on purchases of marketable securities	(257)	(665)
Amortization of operating lease asset	1,945	2,177
Tides Foundation common stock warrant expense	376	377
Stock-based compensation expense	12,671	6,926
Changes in operating assets and liabilities:
Trade and client receivables	(4,773)	(29,978)
Prepaid expenses and other assets	(968)	(585)
Operating lease liability	(925)	(998)
Accounts payable	4,403	(589)
Accrued expenses and other liabilities	7,232	(2,088)
Deferred revenue	1,585	1,317
Net cash provided by (used in) operating activities	6,662	(27,826)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities	(47,748)	(86,567)
Proceeds from maturities of marketable securities	64,000	24,800
Purchases of property and equipment	(5,627)	(7,435)
Internal-use software and platform development costs	(3,559)	(2,182)
Net cash provided by (used in) investing activities	7,066	(71,384)
CASH FLOWS FROM FINANCING ACTIVITIES:
Changes in escrow funds payable	20,832	20,116
Proceeds from exercises of stock options and common stock warrants	16,010	10,340
Proceeds from borrowings on debt	18,000	50,000
Repayment of debt	(21,786)	(26,893)
Proceeds from employee stock purchase plan	2,661	3,577
Net cash provided by financing activities	35,717	57,140
NET CHANGE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	49,445	(42,070)
Cash, cash equivalents, and restricted cash—beginning of period	159,603	230,067
Cash, cash equivalents, and restricted cash—end of period	209,048	187,997
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest	499	714
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING ACTIVITIES:
Property and equipment purchased but not yet paid	478	3,140
Internal-use software and platform development costs incurred but not yet paid	$ 170	$ 0