Property and Equipment, Net (Details) - TOI Parent Inc. - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Property and Equipment, Net
Less: accumulated depreciation	$ (1,721,078)	$ (1,158,403)	$ (474,969)
Total property and equipment, net	3,517,179	2,104,225	1,550,903
Computers and software
Property and Equipment, Net
Property and equipment, gross	$ 739,853	$ 424,099	160,672
Useful lives	60 months	60 months
Office furniture
Property and Equipment, Net
Property and equipment, gross	$ 305,506	$ 270,761	215,375
Useful lives	80 months	80 months
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	$ 3,181,788	$ 1,684,889	1,159,458
Medical equipment
Property and Equipment, Net
Property and equipment, gross	$ 719,035	$ 515,386	397,896
Useful lives	60 months	60 months
Construction in progress
Property and Equipment, Net
Property and equipment, gross	$ 129,306	$ 204,724	29,320
Equipment capital lease assets
Property and Equipment, Net
Property and equipment, gross	$ 162,769	$ 162,769	$ 63,151

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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