v3.26.1
Note 3 - Revenue (Tables)
3 Months Ended
Mar. 31, 2026
Notes Tables  
Disaggregation of Revenue [Table Text Block]
  

Three Months Ended

 
  

March 31,

 
  

2026

  

2025

 

Air Pollution Control

        

Technology solutions

 $755  $571 

Spare parts

  394   251 

Ancillary revenue

  455   481 

Total Air Pollution Control technology revenues

  1,604   1,303 

FUEL CHEM

        

FUEL CHEM technology solutions

  4,476   5,079 

Total Revenues

 $6,080  $6,382 
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Table Text Block]
  

Three Months Ended

 
  

March 31,

 
  

2026

  

2025

 

United States

 $5,247  $5,359 

Foreign Revenues

        

Latin America

  186   348 

Europe

  393   477 

Africa

     38 

Asia

  254   160 

Total Foreign Revenues

  833   1,023 

Total Revenues

 $6,080  $6,382 
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]
  

Three Months Ended

 
  

March 31,

 
  

2026

  

2025

 

Products transferred at a point in time

 $5,325  $5,811 

Products and services transferred over time

  755   571 

Total Revenues

 $6,080  $6,382 
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]
  

As of

 
  

March 31, 2026

  

December 31, 2025

 

Trade receivables

 $3,156  $4,494 

Unbilled receivables

  974   887 

Other short-term receivables

  89   82 

Allowance for credit losses

  (107)  (108)

Total accounts receivable

 $4,112  $5,355