Inventories (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Write-down of potentially obsolete or slow-moving inventories	$ 42,241	$ 518,119	$ 1,501,510
Lower of cost or market adjustment	$ 0	$ 0	$ 166,998

Write-down of potentially obsolete or slow-moving inventories.

No definition available.

Name:	petz_WritedownOfPotentiallyObsoleteOrSlowmovingInventories
Namespace Prefix:	petz_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration