Balance Sheet Detail - Property and Equipment, Net (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 98,330	$ 84,768
Accumulated depreciation	(45,565)	(38,304)
Property and equipment—net	52,765	46,464
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 21,894	19,923
Computer Equipment and Software \| Minimum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	3 years
Computer Equipment and Software \| Maximum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	5 years
Internally Developed Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 38,562	27,099
Internally Developed Software \| Minimum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	3 years
Internally Developed Software \| Maximum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	6 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 6,623	6,425
Property and equipment, Useful Life	5 years
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,358	1,275
Office Equipment \| Minimum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	2 years
Office Equipment \| Maximum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	5 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 29,893	$ 30,046
Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	1 year
Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	10 years

AVALARA, INC. 10-Q