Income taxes - Deferred assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Accrued compensation	$ 3,582	$ 3,821
Deferred revenue	15,878	12,883
Section 174 capitalization	17,947	9,540
Stock-based compensation	18,949	14,960
Federal tax credits	11,739	8,949
Foreign withholding taxes	0	2,782
Net operating losses	54,052	50,794
State tax credits	2,901	2,495
Business interest limitation	9,398	10,054
Operating lease liabilities	3,607	4,347
2026 Notes	4,914	6,627
Other	2,713	3,842
Gross deferred tax assets	145,680	131,094
Valuation allowance	(85,256)	(63,541)
Total deferred tax assets	60,424	67,553
Deferred tax liabilities:
Deferred contract costs	(19,087)	(14,170)
Operating lease right-of-use assets	(2,017)	(3,520)
Intangibles and other	(43,571)	(50,578)
Other	(10)	(300)
Gross deferred tax liabilities	(64,685)	(68,568)
Net deferred tax liabilities	(4,261)	(1,015)
Non-current deferred tax assets	1,691	4,490
Non-current deferred tax liabilities	$ (5,952)	$ (5,505)