Basis of presentation and description of business - Consolidated Statements of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended					6 Months Ended				12 Months Ended
	Jun. 30, 2021		Mar. 31, 2021	Jun. 30, 2020		Jun. 30, 2021	[2]	Jun. 30, 2020		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues [Abstract]
Revenue	$ 86,238		$ 80,727	$ 62,264	[1]	$ 166,965		$ 122,317	[1]	$ 269,132	$ 203,965	$ 147,384
Cost of revenue:
Amortization expense	2,860		2,777	2,678	[1]	5,637		5,355	[1]	10,753	10,266	8,969
Total cost of revenue	19,342		17,256	13,628	[1]	36,598		28,643	[1]	61,008	55,962	49,318
Gross profit	66,896		63,471	48,636	[1]	130,367		93,674	[1]	208,124	148,003	98,066
Operating expenses:
Sales and marketing	32,617		30,167	20,781	[1]	62,784		43,785	[1]	98,885	73,103	53,749
Research and development	17,203		15,626	11,949	[1]	32,829		24,587	[1]	52,513	42,898	31,527
General and administrative	27,508		16,244	6,528	[1]	43,752		17,743	[1]	51,603	31,509	22,444
Amortization expense	5,623		5,627	5,634	[1]	11,250		11,308	[1]	22,575	22,416	21,491
Total operating expenses	82,951		67,664	44,892	[1]	150,615		97,423	[1]	225,576	169,926	129,211
Income (loss) from operations	(16,055)		(4,193)	3,744	[1]	(20,248)		(3,749)	[1]	(17,452)	(21,923)	(31,145)
Interest expense, net	(167)		(55)	(4,690)	[1]	(222)		(9,468)	[1]	(10,741)	(21,423)	(18,203)
Loss on extinguishment of debt										(5,213)
Foreign currency transaction loss	(308)		(218)	(13)	[1]	(526)		(317)	[1]	(722)	(1,252)	(418)
Other income, net	0		0	36	[1]	0		91	[1]	91	220	221
Loss before income tax (provision) benefit	(16,530)		(4,466)	(923)	[1]	(20,996)		(13,443)	[1]	(34,037)	(44,378)	(49,545)
Income tax (provision) benefit	63		(123)	89	[1]	(60)		3,113	[1]	9,955	10,033	11,966
Net loss	$ (16,467)	[1]	$ (4,589)	$ (834)	[1]	$ (21,056)	[1]	$ (10,330)	[1]	$ (24,082)	$ (34,345)	$ (37,579)
Net loss per share, basic (in dollars per share)	$ (0.14)		$ (0.04)	$ (0.01)	[1]	$ (0.18)		$ (0.10)	[1]	$ (0.22)	$ (0.33)	$ (0.37)
Net loss per share, diluted (in dollars per share)	$ (0.14)		$ (0.04)	$ (0.01)	[1]	$ (0.18)		$ (0.10)	[1]	$ (0.22)	$ (0.33)	$ (0.37)
Weighted-average shares used to compute net loss per share, basic (in shares)	117,909,720		117,386,322	102,862,404	[1]	117,649,467		102,861,475	[1]	108,908,597	102,752,092	102,325,465
Weighted-average shares used to compute net loss per share, diluted (in shares)	117,909,720		117,386,322	102,862,404	[1]	117,649,467		102,861,475	[1]	108,908,597	102,752,092	102,325,465
Subscription
Revenues [Abstract]
Revenue	$ 80,718		$ 74,482	$ 58,600	[1]	$ 155,200		$ 112,804	[1]	$ 248,879	$ 175,118	$ 113,867
Cost of revenue:
Cost of revenue	13,875		12,014	8,740	[1]	25,889		17,988	[1]	39,529	31,457	24,099
Operating expenses:
Net loss										(24,082)
Services
Revenues [Abstract]
Revenue	3,929		4,003	2,632	[1]	7,932		6,719	[1]	14,519	19,014	20,201
Cost of revenue:
Cost of revenue	2,607		2,465	2,210	[1]	5,072		5,300	[1]	10,726	14,239	16,250
License
Revenues [Abstract]
Revenue	$ 1,591		2,242	1,032	[1]	$ 3,833		2,794	[1]	5,734	9,833	13,316
As Previously Reported
Revenues [Abstract]
Revenue			81,168	62,231				122,621		269,451	204,027	146,562
Cost of revenue:
Amortization expense			2,777	2,678				5,355		10,753	10,266	8,969
Total cost of revenue			17,256	13,647				28,658		60,788	56,029	49,303
Gross profit			63,912	48,584				93,963		208,663	147,998	97,259
Operating expenses:
Sales and marketing			29,332	20,202				42,484		96,251	71,006	51,976
Research and development			15,626	11,929				24,546		52,431	42,829	31,515
General and administrative			16,105	6,603				17,892		51,904	32,003	22,270
Amortization expense			5,627	5,634				11,308		22,575	22,416	21,491
Total operating expenses			66,690	44,368				96,230		223,161	168,254	127,252
Income (loss) from operations			(2,778)	4,216				(2,267)		(14,498)	(20,256)	(29,993)
Interest expense, net			(55)	(4,690)				(9,468)		(10,741)	(21,423)	(18,203)
Loss on extinguishment of debt										(5,213)
Foreign currency transaction loss			(171)	(13)				(317)		(722)	(1,252)	(418)
Other income, net			0	36				91		91	220	221
Loss before income tax (provision) benefit			(3,004)	(451)				(11,961)		(31,083)	(42,711)	(48,393)
Income tax (provision) benefit			(65)	28				3,248		8,312	10,111	12,137
Net loss			$ (3,069)	$ (423)				$ (8,713)		$ (22,771)	$ (32,600)	$ (36,256)
Net loss per share, basic (in dollars per share)			$ (0.03)	$ (0.00)				$ (0.08)		$ (0.21)	$ (0.32)	$ (0.35)
Net loss per share, diluted (in dollars per share)			$ (0.03)	$ (0.00)				$ (0.08)		$ (0.21)	$ (0.32)	$ (0.35)
Weighted-average shares used to compute net loss per share, basic (in shares)			117,386,322	102,862,404				102,861,475		108,908,597	102,752,092	102,325,465
Weighted-average shares used to compute net loss per share, diluted (in shares)			117,386,322	102,862,404				102,861,475		108,908,597	102,752,092	102,325,465
As Previously Reported | Subscription
Revenues [Abstract]
Revenue			$ 74,923	$ 58,748				$ 113,366		$ 249,192	$ 175,189	$ 113,040
Cost of revenue:
Cost of revenue			12,014	8,762				18,010		39,323	31,539	24,088
Operating expenses:
Net loss										(22,771)
As Previously Reported | Services
Revenues [Abstract]
Revenue			4,003	2,451				6,461		14,525	19,008	20,206
Cost of revenue:
Cost of revenue			2,465	2,207				5,293		10,712	14,224	16,246
As Previously Reported | License
Revenues [Abstract]
Revenue			2,242	1,032				2,794		5,734	9,830	13,316
Adjustments | Commissions
Revenues [Abstract]
Revenue			0	0				0		0	0	0
Cost of revenue:
Amortization expense			0	0				0		0	0	0
Total cost of revenue			0	0				0		0	0	0
Gross profit			0	0				0		0	0	0
Operating expenses:
Sales and marketing			835	544				1,234		2,497	1,991	1,755
Research and development			0	0				0		0	0	0
General and administrative			0	0				0		0	0	0
Amortization expense			0	0				0		0	0	0
Total operating expenses			835	544				1,234		2,497	1,991	1,755
Income (loss) from operations			(835)	(544)				(1,234)		(2,497)	(1,991)	(1,755)
Interest expense, net			0	0				0		0	0	0
Loss on extinguishment of debt										0
Foreign currency transaction loss			0	0				0		0	0	0
Other income, net			0	0				0		0	0	0
Loss before income tax (provision) benefit			(835)	(544)				(1,234)		(2,497)	(1,991)	(1,755)
Income tax (provision) benefit			(70)	142				311		619	488	428
Net loss			(905)	(402)				(923)		(1,878)	(1,503)	(1,327)
Adjustments | Commissions | Subscription
Revenues [Abstract]
Revenue			0	0				0		0	0	0
Cost of revenue:
Cost of revenue			0	0				0		0	0	0
Operating expenses:
Net loss										(1,878)
Adjustments | Commissions | Services
Revenues [Abstract]
Revenue			0	0				0		0	0	0
Cost of revenue:
Cost of revenue			0	0				0		0	0	0
Adjustments | Commissions | License
Revenues [Abstract]
Revenue			0	0				0		0	0	0
Adjustments | Other
Revenues [Abstract]
Revenue			(441)	33				(304)		(319)	(62)	822
Cost of revenue:
Amortization expense			0	0				0		0	0	0
Total cost of revenue			0	(19)				(15)		220	(67)	15
Gross profit			(441)	52				(289)		(539)	5	807
Operating expenses:
Sales and marketing			0	35				67		137	106	18
Research and development			0	20				41		82	69	12
General and administrative			139	(75)				(149)		(301)	(494)	174
Amortization expense			0	0				0		0	0	0
Total operating expenses			139	(20)				(41)		(82)	(319)	204
Income (loss) from operations			(580)	72				(248)		(457)	324	603
Interest expense, net			0	0				0		0	0	0
Loss on extinguishment of debt										0
Foreign currency transaction loss			(47)	0				0		0	0	0
Other income, net			0	0				0		0	0	0
Loss before income tax (provision) benefit			(627)	72				(248)		(457)	324	603
Income tax (provision) benefit			12	(81)				(446)		1,024	(566)	(599)
Net loss			(615)	(9)				(694)		567	(242)	4
Adjustments | Other | Subscription
Revenues [Abstract]
Revenue			(441)	(148)				(562)		(313)	(71)	827
Cost of revenue:
Cost of revenue			0	(22)				(22)		206	(82)	11
Operating expenses:
Net loss										567
Adjustments | Other | Services
Revenues [Abstract]
Revenue			0	181				258		(6)	6	(5)
Cost of revenue:
Cost of revenue			0	3				7		14	15	4
Adjustments | Other | License
Revenues [Abstract]
Revenue			$ 0	$ 0				$ 0		$ 0	$ 3	$ 0

[1] Certain prior period amounts have been revised to correct immaterial errors. See Note 1 for more information.

[2] Includes the three months ended March 31, 2021, which has been revised to correct immaterial errors. See Note 1 for more information.