Net Loss Per Share - Summary of Computation of Basic and Diluted Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net (loss) income from continuing operations	$ (60,332)	$ (140,483)	$ 3,870
Net (loss) income from discontinued operations, net of tax	(28,990)	(60,843)	22,006
Less: net income attributable to the redeemable noncontrolling interest	0	164	936
Less: net (loss) income attributable to noncontrolling interests	(743)	(533)	228
Allocation of undistributed earnings to convertible preferred stock	0	0	24,712
Net loss attributable to holders of Class A, Class B, and Class C common stock for basic net loss per share	(88,579)	(200,957)	0
Add: interest on Notes	0	0	1,317
Deduct: change in fair value of derivative liability	0	0	(26,745)
Reallocation of undistributed earnings to convertible preferred stock	0	0	24,712
Net loss attributable to holders of Class A, Class B, and Class C common stock for diluted net loss per share	(88,579)	(200,957)	(716)
Amounts attributable to BuzzFeed, Inc for net loss per common share, basic:
Net (loss) income from continuing operations, basic	(59,589)	(140,114)	0
Net (loss) income from discontinued operations, net of tax, basic	(28,990)	(60,843)	0
Net (loss) income attributable to BuzzFeed, Inc., basic	(88,579)	(200,957)	0
Amounts attributable to BuzzFeed, Inc for net loss per common share, diluted:
Net (loss) income from continuing operations, diluted	(59,589)	(140,114)	(716)
Net (loss) income from discontinued operations, net of tax, diluted	(28,990)	(60,843)	0
Net (loss) income attributable to BuzzFeed, Inc. diluted	$ (88,579)	$ (200,957)	$ (716)
Denominator:
Weighted average common shares outstanding, basic (in shares)	143,062	138,148	27,048
Impact of assumed conversion of Notes (in shares)	0	0	953
Weighted average common shares outstanding, diluted (in shares)	143,062	138,148	28,001
Net loss per common share, basic:
Continuing operations basic (in dollars per share)	$ (0.42)	$ (1.01)	$ 0
Discontinued operations basic (in dollars per share)	(0.20)	(0.44)	0
Net loss per common share, Basic (in dollars per share)	(0.62)	(1.45)	0
Net loss per common share, diluted:
Continuing operations diluted (in dollars per share)	(0.42)	(1.01)	(0.03)
Discontinued operations diluted (in dollars per share)	(0.20)	(0.44)	0
Net loss per common share, Diluted (in dollars per share)	$ (0.62)	$ (1.45)	$ (0.03)