Note 2 - Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2025

Notes to Financial Statements

Significant Accounting Policies [Text Block]

2.     Summary of Significant Accounting Policies

Investments

The Company's investment policy provides for $20,000 in funds at BMO Harris Bank, N.A. (BMO Harris) to be invested in debt securities. The funds are held in money market funds until they are invested in those securities. A portion of the funds invested are restricted as collateral under the Investment Collateral Security agreement (see Note 10). At March 31, 2025, the amount of funds collateralized under the Investment Collateral Security agreement is $3,186 relating to existing standby letters of credit that is comprised of $2,608 with varying maturity dates that expire no later than March 31, 2026 and $578 with the latest maturity date no later than  February 28, 2027.

We consider all highly liquid debt investments with original maturities from the date of purchase of three months or less as cash equivalents. Cash equivalents include investments in money market funds. Carrying value of cash equivalents approximates fair value due to the maturities of three months or less.

Our investments in debt securities consist of United States (US) Treasury securities, including Notes, Bonds, and Bills, and US Government Agency securities, which are designated as held-to-maturity (HTM) and stated at amortized cost. The Company has the positive intent and ability to hold these investments to maturity and does not expect to sell any debt securities before maturity to settle an obligation under the Investment Collateral Security agreement. The original maturities of our HTM investments range from three to thirty-six months. HTM debt investments with original maturities of approximately three months or less from the date of purchase are classified within cash and cash equivalents. HTM debt investments with original maturities at the date of purchase greater than approximately three months and remaining maturities of less than one year are classified as short-term investments. HTM debt investments with remaining maturities beyond one year are classified as long-term investments. Interest income, including amortization of premium and accretion of discount, is included on the Condensed Consolidated Statements of Operations in Interest income under the effective yield method. Accrued interest is included in Prepaid expenses and other current assets on the Condensed Consolidated Balance Sheets. Due to the creditworthiness of the entities issuing these securities, there is no impairment recorded related to the unrealized losses.

The following table provides the amortized cost, gross unrealized gains and losses, and fair value of our HTM debt securities:

	As of
Held-to-maturity debt securities:	March 31, 2025			December 31, 2024
Amortized cost	$	19,349		$	21,059
Gross unrecognized gains		59			50
Gross unrecognized losses		(12	)		(33	)
Fair value	$	19,396		$	21,076

The following table provides the amortized cost and fair value of debt securities by maturities at March 31, 2025:

	Amortized Cost		Fair Value
Within one year	$	9,968	$	9,984
After one year through two years		8,400		8,423
After two years through three years		981		989
Total	$	19,349	$	19,396

Inventories

Inventories consist primarily of equipment constructed for resale and spare parts and are stated at the lower of cost or net realizable value, using the weighted-average cost method. At  March 31, 2025 and December 31, 2024, inventory included equipment constructed for resale of $176 and spare parts, net of reserves, of $358 and $221, respectively. Usage is recorded in cost of sales in the period that parts were issued to a project, used to service equipment, or sold to customers. Equipment constructed for resale that is in process is recorded in Other assets. In process equipment for inventory recorded as Other assets was $46 and $44 as of  March 31, 2025 and December 31, 2024, respectively. Inventories are periodically evaluated to identify obsolete or otherwise impaired parts and are written off when management determines usage is not probable. The Company estimates the balance of excess and obsolete inventory by analyzing inventory by age using the last used and original purchase dates and existing sales pipeline for which the inventory could be used.

Allowance for Credit Losses

The Company accounts for expected credit losses under Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) ASU 2019-10, Financial Instruments - Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842). This guidance requires the measurement of all expected losses based on historical experience, current conditions and reasonable and supportable forecasts. For trade receivables and other financial instruments, we are required to use a forward-looking expected loss model rather than the incurred loss model for recognizing credit losses which reflects losses that are probable. 

For the general risk categories, the Company uses historical losses over a fixed period, excluding certain write-off activity that was not considered a credit loss event, to determine the historical credit loss. Historical loss rates are then adjusted to consider current economic conditions and past, current, and future events and circumstances when determining expected credit losses. Investments in financial assets issued by US Government and Government Agency are considered as having zero expected credit losses and are excluded from the allowance for credit loss calculation.

The following table provides the roll forward of the allowance for credit losses:

At January 1, 2024	$	111
Provision charged to expense		—
(Write-offs) / Recoveries		(5	)
At December 31, 2024	$	106
Provision charged to expense		—
(Write-offs) / Recoveries		—
At March 31, 2025	$	106