Receivables
 12 Months Ended
Dec. 31, 2021
Receivables [Abstract]  
Receivables
RECEIVABLES
Receivables were comprised of the following:
December 31,
(In thousands)20212020
Billed receivables$104,074 $102,045 
Unbilled receivables (contract assets)239,979 203,127 
Other 4,552 9,787 
Total Receivables$348,605 $314,959 
As of December 31, 2021 and 2020, 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 the Company’s billed receivables are with the U.S. government, the Company does not believe it has 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 expect to bill customers for the majority of the December 31, 2021 contract assets during 2022. Changes in the balance of receivables are primarily due to the timing differences between our performance and customer payments.