Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Income Taxes - Schedule of Reconciliation of the Statutory Federal Income Tax Expense (Details) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 22, 2017	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Total income tax expense (benefit)						$ 0	$ 0
U.S. federal provision at statutory rate				21.00%	21.00%	21.00%	21.00%
State income taxes, net of federal benefit						2.90%	3.70%
Tax credits						1.90%	2.20%
Permanent items						(7.40%)	(3.90%)
Uncertain tax benefits						(0.90%)	(1.10%)
Change in valuation allowance						(17.50%)	(21.90%)
Effective tax rate				0.00%	0.00%	0.00%	0.00%
Gores Metropoulos, Inc.
Income tax expense at the federal statutory rate						$ 1,446,224	$ (4,617)
State income taxes - net of federal income tax benefits						(29,220)	(1,018)
Change in valuation allowance						24,603	$ 5,635
Total income tax expense (benefit)		$ (46,571)	$ 405,292	$ 171,781	$ 1,132,843	$ 1,441,607
U.S. federal provision at statutory rate	21.00%
Effective tax rate				21.00%