Organization and Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands			12 Months Ended
	Feb. 12, 2019 USD ($) tranche item	May 24, 2018 USD ($) item tranche shares	Dec. 31, 2020 USD ($) segment customer item country shares	Dec. 31, 2019 USD ($) customer country shares	Dec. 31, 2018 USD ($) customer country shares
Summary Of Significant Accounting Policy [Line Items]
Restricted cash balance			$ 62	$ 56
Impairment charge					$ 2,000
Number of revenue sources | item			2
Allowance for doubtful accounts			$ 3,376	1,567
Cost of sales			$ 264,672	223,574	161,485
Warranty period			1 year
Research and development costs			$ 123,195	100,721	$ 76,856
Number of depository institutions | item			4
Aggregate balances in depository institution accounts			$ 145,100
Cash surrender value of corporate-owned life insurance policies			$ 4,654	$ 4,214
Number of reportable segments of company | segment			2
Market capitalization goal for such tranche		$ 2,500,000
Market capitalization goal increment		$ 1,000,000
New option granted (in shares) | shares			0	0	0
Risk-free interest rate (as percentage)			2.98%
Expected life of options			9 years 9 months 3 days
Adoption of Topic 326, cumulative-effect adjustment to retained earnings			$ 768
Additional credit loss expense			1,215
COVID-19
Summary Of Significant Accounting Policy [Line Items]
Additional credit loss expense			$ 900
Net Sales | Geographic Concentration Risk
Summary Of Significant Accounting Policy [Line Items]
Number of countries outside the U.S. representing more than 10% of total net sales | country			0	0	0
Net Sales | Customer Concentration Risk
Summary Of Significant Accounting Policy [Line Items]
Number of major customers | customer			0	0	0
Accounts and notes receivable and contract assets | Customer Concentration Risk
Summary Of Significant Accounting Policy [Line Items]
Number of major customers | customer			0	0
Advertising
Summary Of Significant Accounting Policy [Line Items]
Cost of sales			$ 1,300	$ 900	$ 1,100
Performance Shares
Summary Of Significant Accounting Policy [Line Items]
New option granted (in shares) | shares		6,365,856
Illiquidity discount (as percentage)			9.20%
Post-vest holding period			2 years 6 months
Stock Options
Summary Of Significant Accounting Policy [Line Items]
Restricted stock, expiration period			10 years
New option granted (in shares) | shares			0	0	6,366,000
Chief Executive Officer
Summary Of Significant Accounting Policy [Line Items]
Restricted stock, expiration period		10 years
Number of vesting tranches of share-based awards | tranche		12
Number of performance goals, revenue | item		8
Number of performance goals, adjusted EBITDA | item		8
2019 eXponential Stock Performance Plan | eXponential Stock Units
Summary Of Significant Accounting Policy [Line Items]
Restricted stock, expiration period	9 years
Number of vesting tranches of share-based awards | tranche	12
Number of performance goals, revenue | item	8
Number of performance goals, adjusted EBITDA | item	8
Market capitalization goal for such tranche	$ 2,500,000
Market capitalization goal increment	$ 1,000,000
New option granted (in shares) | shares			300,000
Post-vest holding period			2 years 6 months
Expected dividend yield (as percentage)			0.00%
Minimum | 2019 eXponential Stock Performance Plan | eXponential Stock Units
Summary Of Significant Accounting Policy [Line Items]
Liquidity discount (as percentage)			10.30%
Risk-free interest rate (as percentage)			0.53%
Expected life of options			7 years 3 months 18 days
Expected volatility (as percentage)			46.37%
Maximum | 2019 eXponential Stock Performance Plan | eXponential Stock Units
Summary Of Significant Accounting Policy [Line Items]
Liquidity discount (as percentage)			17.40%
Risk-free interest rate (as percentage)			1.53%
Expected life of options			8 years
Expected volatility (as percentage)			51.96%
Design of New Headquarters
Summary Of Significant Accounting Policy [Line Items]
Impairment charge			$ 700	$ 700
Office Improvements and Remodeling
Summary Of Significant Accounting Policy [Line Items]
Impairment charge			$ 500
Enterprise Resource Planning System
Summary Of Significant Accounting Policy [Line Items]
Impairment charge				$ 1,300