Loss per Share (FY) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Earnings Per Share [Abstract]

Loss per Share, Basic and Diluted

The following table sets forth the computation of the basic and diluted net loss per share attributable to the Class 1 and Class 2 common stockholders (in thousands, except per share amounts):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2021			2020			2021			2020
Numerator:
Net loss	$	(11,194	)	$	(2,715	)	$	(44,724	)	$	(12,714	)
Denominator:
Weighted-average common shares outstanding		158,316			99,948			154,303			99,876
Net loss per share attributable to common stockholders, basic and diluted	$	(0.07	)	$	(0.03	)	$	(0.29	)	$	(0.13	)

The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders for the years ended December 31, 2020, 2019 and 2018 (in thousands, except per share amounts), as retroactively adjusted (refer to Note 1):

	December 31,
	2020			2019			2018
Numerator:
Net loss	$	(17,027	)	$	(22,803	)	$	(18,231	)
Denominator:
Weighted-average common shares outstanding		100,022,546			99,272,157			97,951,673
Net loss per share attributable to common stockholders, basic and diluted	$	(0.17	)	$	(0.23	)	$	(0.19	)

Antidilutive Securities Excluded from Computation of Diluted Earnings per Share

Potentially dilutive securities that were not included in the diluted per share calculations because they would be antidilutive, were as follows as of the dates presented based on the underlying shares and not considering all factors that would be involved in determining the common stock equivalents (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Stock options		20,347		16,373		20,347		16,373
Restricted stock units		646		—		646		—
Warrants		12,498		12,500		12,498		12,500
		33,491		28,873		33,491		28,873

Potentially dilutive securities, as retroactively adjusted (refer to Note 1), that were not included in the diluted per share calculations because they would be antidilutive, were as follows as of the dates presented, based on the underlying shares and not considering all factors that would be involved in determining the common stock equivalents:

	December 31,
	2020		2019		2018
Options to purchase common stock		16,170,737		11,653,411		12,591,770
Series C Warrants		105,005		105,005		105,005
		16,275,742		11,758,416		12,696,775