Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities
Net income	$ 32,116	$ 24,550
Reconciliation of net income to net cash provided by operating activities
Deferred income taxes	4,324	5,360
Change in earn-out liability	72	(366)
Depreciation and amortization of property and equipment	9,474	8,143
Amortization of intangible assets	3,985	3,897
Provision for credit losses	4,198	2,429
Stock-based compensation	14,246	11,316
Other, net	(16)	(551)
Changes in assets and liabilities
Accounts receivable	(4,551)	(3,670)
Deferred costs	(1,129)	(151)
Other current and non-current assets	2,612	(820)
Accounts payable	1,357	181
Accrued compensation	(3,989)	(3,716)
Accrued expenses	(3)	(84)
Deferred revenue	3,961	4,929
Operating leases	(1,128)	(487)
Net cash provided by operating activities	65,529	50,960
Cash flows from investing activities
Purchases of property and equipment	(11,639)	(8,387)
Purchases of investments	(67,636)	(61,967)
Maturities of investments	47,300	55,225
Acquisitions of businesses and intangible assets, net of cash acquired		(11,500)
Net cash used in investing activities	(31,975)	(26,629)
Cash flows from financing activities
Repurchases of common stock	(18,950)	(14,966)
Net proceeds from exercise of options to purchase common stock	14,143	5,273
Net proceeds from employee stock purchase plan	1,645	1,155
Payment for earn-out liability	(688)
Net cash used in financing activities	(3,850)	(8,538)
Effect of foreign currency exchange rate changes	(26)	75
Net increase in cash and cash equivalents	29,678	15,868
Cash and cash equivalents at beginning of period	179,252	133,859
Cash and cash equivalents at end of period	$ 208,930	$ 149,727