Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Property and Equipment (FY) (Details) - USD ($)	12 Months Ended
Property and Equipment (FY) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16,124,395	$ 14,813,243
Less: accumulated depreciation and amortization	(8,736,975)	(5,657,718)
Property and equipment, net	7,387,420	9,155,525		$ 10,031,000
Depreciation and amortization expense	3,079,257	1,776,983	$ 1,266,508
Foreign Locations
Property, Plant and Equipment [Line Items]
Property and equipment, net	78,921	174,361
Computer Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,117,299	6,585,289
Capitalized Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,122,650	5,122,650
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,285,880	1,213,132
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,598,566	$ 1,892,172