Revenues

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

Revenues

Revenues

Contract Assets and Liabilities

Contract assets are comprised of unbilled receivables and are included in Receivables, net in the Consolidated Balance Sheets. Unbilled receivables represent a conditional right to consideration in exchange for goods or services transferred to a customer.

Trade receivables represent an unconditional right to consideration in exchange for goods or services transferred to a customer. The Company invoices its customers in accordance with the terms of the contract. Credit terms are generally net 30 from the date of invoice. The timing between the satisfaction of performance obligations and when payment is due from the customer is generally not significant. The Company records allowances for doubtful trade receivables when it is probable that the balances will not be collected.

Contract liabilities are comprised of deferred revenue, which represents an obligation to transfer goods or services to a customer for which the Company has received consideration from the customer and, if deliverable within one year or less, is included in Other current liabilities in the Consolidated Balance Sheets and, if deliverable outside of one year, is included in Other long-term liabilities in the Consolidated Balance Sheets.

Trade receivables, net

The following table shows the components of Trade receivables, net:

	As of December 31,
(in thousands)	2020		2019
Trade receivables	$	12,241	$	8,057
Less: Allowance for doubtful accounts	(37)		(627)
Trade receivables, net	$	12,204	$	7,430

During the years ended December 31, 2020 and 2019, the Company recognized zero and $0.1 million, respectively, as bad debt expense related to specific accounts whose ultimate collection was in doubt.

Upfront Customer Consideration

As described in Note 3, as of September 30, 2020, the Company recorded an asset for Upfront Customer Consideration of $7.6 million in connection with the Supply Agreement. The amount is included in Other long-term assets, net on the Company's Consolidated Balance Sheet as of December 31, 2020. The Upfront Customer Consideration is being amortized on a straight-line basis as a reduction to revenue over the expected 15-year contractual period of the Supply Agreement.

Disaggregation of Revenue and Earnings from Equity Method Investments

For the years ended December 31, 2020 and 2019, all performance obligations related to revenues recognized were satisfied at a point in time. The Company disaggregates its revenues by its major components as well as between its two operating segments, which are further discussed in Note 19 to the consolidated financial statements. The Company does not disaggregate revenue by geographic region as revenue is generated primarily from customers in the United States; however, in the APT segment for the year ended December 31, 2020, approximately 15% of APT revenue was generated in Canada. The following tables disaggregate revenues by major source for the year ended December 31, 2020 and 2019 (in thousands):

	Year ended December 31, 2020
	Segment
(in thousands)	APT		RC		Total
Revenue component
Consumables	$	48,122	$	—	$	48,122
License royalties, related party	—		13,440		13,440
Other	15		—		15
Revenues from customers	48,137		13,440		61,577
Earnings from equity method investments	—		30,978		30,978
Total revenues and earnings from equity method investments	$	48,137	$	44,418	$	92,555

	Year ended December 31, 2019
	Segment
(in thousands)	APT		RC		Total
Revenue component
Consumables	$	53,187	$	—	$	53,187
License royalties, related party	—		16,899		16,899
Revenues from customers	53,187		16,899		70,086
Earnings from equity method investments	—		69,176		69,176
Total revenues and earnings from equity method investments	$	53,187	$	86,075	$	139,262

As further discussed in Note 19, as of December 31, 2020 the Company had a change in reportable segments. The Company has recast the segment information above for the year ended December 31, 2019 to be consistent with the new reportable segments as of December 31, 2020.