Under ASC 326 – Financial Instruments – Credit Losses, the Company estimates credit losses for the contractual life of assets that are measured at amortized cost and are within the scope of this guidance, which includes accounts receivable, net investment in sales-type leases, contract assets under the revenue recognition model and outstanding notes receivable. Where appropriate, the Company pools assets if similar risk characteristics exist. Additionally, the Company analyzes its available-for-sale debt securities for impairment and records a credit loss allowance as needed.

The Company records accounts receivable in the normal course of business as products are shipped or services are performed and invoiced, but payment has not yet been remitted by the customer. As of January 1, 2020 and September 30, 2020, the Company’s outstanding accounts receivable balance was $90.5 million and $100.2 million, respectively. The Company assessed the need for an allowance for credit losses related to its outstanding accounts receivable as of September 30, 2020 and January 1, 2020 using the historical loss-rate method as well as assessing asset-specific risks. The Company’s historical losses related to accounts receivable have been immaterial as evidenced by its historical allowance and write-offs due to uncollectability. The assessment of asset-specific risks included the evaluation of relevant available information, from internal and external sources, relating to current conditions that may affect a customer’s ability to pay, such as the customer’s current financial condition, credit rating by geographic location, as provided by a third party and/or by customer, if needed, and overall macro-economic conditions in which the customer operates. The Company pooled assets by geographic location to determine if an allowance should be applied to its accounts receivable balance, assessing the specific country risk rating and overall economics of that particular country. If elevated risk existed, or customer specific risk indicated the accounts receivable balance was at risk, the Company further analyzed the need for an allowance related to specific accounts receivable balances. Additionally, the Company determined that significant changes to customer country risk rating from period-to-period and from the end of the prior year to the end of the current quarter would require further review and analysis by the Company.

Accounts receivable balances are considered past due when payment has not been received by the date indicated on the relevant invoice or based on agreed upon terms between the customer and the Company.

No allowance for credit loss was recorded on January 1, 2020 (the “implementation date”) or during the three and nine months ended September 30, 2020 related to accounts receivable. The Company’s allowance for credit losses related to accounts receivable was $38 thousand as of September 30, 2020 and December 31, 2019, all of which was expensed prior to January 1, 2020.

The Company records contract assets when it has recognized revenue but has not yet billed the customer. As of January 1, 2020 and September 30, 2020, the Company’s outstanding contract asset balance was $2.8 million and $1.0 million, respectively, which is included in other receivables on the Condensed Consolidated Balance Sheets as of December 31, 2019 and September 30, 2020. The Company assessed the need for an allowance for credit losses related to its outstanding contract assets as of September 30, 2020 and January 1, 2020 using the historical loss-rate method as well as asset-specific risks. The Company’s historical losses related to contract assets receivable have been immaterial as evidenced by historical write-offs due to uncollectability. Asset-specific risk included the evaluation of relevant available information, from internal and external sources, relating to current conditions that may affect a customer’s ability to pay once invoiced, such as the customer’s financial condition, credit rating by geographic location as provided by a third party and/or by customer, if needed, and overall macro-economic conditions in which the customer operates. The Company pooled assets by geographic location to determine if an allowance should be applied to its contract asset balance, assessing the specific country risk rating and overall economics of that particular country. If elevated risk existed, or customer specific risk indicated the contract balance was at risk, the Company further analyzed the need for an allowance related to specific customer balances. Additionally, the Company determined that significant changes to customer country risk rating from period-to-period and from the end of the prior year to the end of the current quarter would be subject to further review and analysis by the Company.

No allowance for credit loss was recorded on the implementation date or during the three and nine months ended September 30, 2020 related to contract assets.

The Company is the lessor in sales-type lease arrangements for network equipment. As of January 1, 2020 and September 30, 2020, the Company’s outstanding net investment in sales-type leases was $1.6 million and $1.0 million, respectively, which is included in other receivables and other assets on the Condensed Consolidated Balance Sheets as of December 31, 2019 and September 30, 2020. The Company assessed the need for an allowance for credit losses related to future receivables under its outstanding sales-type leases as of September 30, 2020 and January 1, 2020 using the historical loss-rate method as well as asset-specific risks. The Company’s historical losses related to contract assets receivable have been immaterial as evidenced by historical write-offs due to uncollectability. Asset-specific risk included the evaluation of relevant available information, from internal and external sources, relating to current conditions that may affect a customer’s ability to pay once invoiced, such as the customer’s financial condition, credit rating by geographic location as provided by a third party and/or by customer, if needed, and overall macro-economic conditions in which the customer operates.

The following table presents amortized cost basis in sales-type leases based on payment activity:

	Sales-Type Leases Amortized Cost Basis by Origination Year
(In thousands)	2020		2019		2018		2017		2016		Prior		Total
Payment performance
Performing	$	58	$	227	$	426	$	153	$	89	$	3	$	956
Non-performing		—		—		—		—		—		—		—
Total	$	58	$	227	$	426	$	153	$	89	$	3	$	956

Sales-type lease receivables are considered past due when payment has not been received based on agreed upon terms between the customer and the Company. No allowance for credit loss was recorded on the implementation date or during the three and nine months ended September 30, 2020 related to sales-type leases.

The Company has a secured loan receivable totaling $0.9 million as of January 1, 2020 and September 30, 2020, which originated in February 2019, and is included in long-term investments on the Condensed Consolidated Balance Sheets as of September 30, 2020 and December 31, 2019. The Company assessed the need for an allowance for credit loss related to its secured loan receivable as of September 30, 2020 and January 1, 2020 using the historical loss-rate method as well as asset-specific risks. There have been no historical losses related to this receivable. Asset-specific risks included the evaluation of relevant available information, from internal and external sources, relating to current conditions that may affect the customer’s ability to repay the loan upon maturity, such as the customer’s current financial condition, credit rating specific to the customer as determined by a third party and current overall economic conditions, as well as a Company valuation prepared by a third party which was based on reasonable and supportable forecasts as provided by management. Accrued interest receivable on the secured loan receivable, which is included in other receivables on the Condensed Consolidated Balance Sheets as of September 30, 2020 and December 31, 2019, totaled $24 thousand and $0 as of January 1, 2020 and September 30, 2020, respectively, and was excluded from the estimate of credit losses for both periods based on the Company’s accounting policy election.

No allowance for credit loss was recorded on the implementation date or during the three and nine months ended September 30, 2020 related to the secured loan receivable.

The Company did not have any off-balance sheet arrangements as of January 1, 2020 or September 30, 2020.

As of January 1, 2020 and September 30, 2020, the Company’s available-for-sale debt securities totaled $37.7 million and $44.9 million, respectively. These securities were analyzed at the individual investment level, by CUSIP, to limit credit losses, if applicable, to reflect only the amount by which the fair value of the security was less than its amortized cost. The Company noted that, as of January 1, 2020 and September 30, 2020, there was no intent to sell any of its available-for-sale debt securities before maturity, and, therefore, the Company assessed the need for an allowance for each of its available-for-sale debt securities in which the fair value was less than its amortized cost as of January 1, 2020 and September 30, 2020. Accrued interest receivable on available-for-sale debt securities, which is included in other receivables on the Condensed Consolidated Balance Sheets as of September 30, 2020 and December 31, 2019, totaled $0.1 million as of January 1, 2020 and September 30, 2020, and was excluded from the estimate of credit losses for both periods based on the Company’s accounting policy election. Income generated from available-for-sale debt securities was recorded as interest and dividend income in the Condensed Consolidated Statements of Income (Loss).

The Company had 45 positions in available-for-sale debt securities that were in an unrealized loss position as of September 30, 2020, which are presented in the table below:

(In thousands)	Continuous Unrealized Loss Position for Less than 12 Months					Continuous Unrealized Loss Position for 12 Months or Greater				Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate bonds		—		—			—		—		—		—
Municipal fixed-rate bonds		394		(1	)		—		—		394		(1	)
Asset-backed bonds		396		—			—		—		396		—
Mortgage/Agency-backed bonds		3,199		(11	)		—		—		3,199		(11	)
U.S. government bonds		800		—			—		—		800		—
Foreign government bonds		75		—			—		—		75		—
Total	$	4,864	$	(12	)	$	—	$	—	$	4,864	$	(12	)

The following table outlines the available-for-sale debt securities in an unrealized loss position as of January 1, 2020:

(In thousands)	Continuous Unrealized Loss Position for Less than 12 Months					Continuous Unrealized Loss Position for 12 Months or Greater					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate bonds		203		—			—		—			203		—
Municipal fixed-rate bonds		930		—			—		—			930		—
Asset-backed bonds		797		(3	)		—		—			797		(3	)
Mortgage/Agency-backed bonds		2,594		(6	)		136		(2	)		2,730		(8	)
U.S. government bonds		4,070		(9	)		—		—			4,070		(9	)
Foreign government bonds		371		(1	)		—		—			371		(1	)
Total	$	8,965	$	(19	)	$	136	$	(2	)	$	9,101	$	(21	)

For those available-for-sale debt securities whose fair value was less than its amortized cost basis, the Company analyzed additional criteria such as adverse conditions specifically related to the security, an industry or geographic area, failure of the issuer of the security to make scheduled interest or principal payments, if applicable, and any changes to the rating of the security by a rating agency to determine if a credit loss existed. The Company used information provided by its investment manager to determine if any scheduled interest or principal payments had not been received and used a third party to determine if any changes to credit ratings had occurred. The Company noted that all principal and interest payments had been received as scheduled and that there had been no changes in credit ratings year-over-year or period-over-period that warranted further review.

No allowance for credit loss was recorded on the implementation date or during the three and nine months ended September 30, 2020 related to the Company’s available-for-sale debt securities.