Receivables
 9 Months Ended
Oct. 02, 2020
Receivables [Abstract]  
Receivables
RECEIVABLES
    Receivables were comprised of the following:
(In thousands)October 2, 2020December 31, 2019
Billed receivables$59,445 $71,068 
Unbilled receivables (contract assets)199,301 186,365 
Other 9,397 11,711 
Total receivables$268,143 $269,144 
    As of October 2, 2020 and December 31, 2019, substantially all billed receivables are due from the U.S. Government, either directly as prime contractor to the U.S. Government or as subcontractor to another prime contractor to the U.S. Government. Because our billed receivables are with the U.S. Government, we do not believe they represent a material credit risk exposure.
    Unbilled receivables are contract assets that represent revenue recognized on long-term contracts in excess of amounts billed as of the balance sheet date. We estimate that approximately $6.1 million of our unbilled receivables as of October 2, 2020 may not be collected within the next 12 months. These amounts relate to the timing of the U.S. Government review of indirect rates and contract line item realignments with our customers. Changes in the balance of receivables are primarily due to the timing differences between our performance and customers' payments.