Accounts Receivable

6 Months Ended

Jan. 31, 2021

Accounts receivable consist of the following at:


	January 31, 2021		July 31, 2020
Receivables from commercial and international customers	$	77,551,000	67,109,000
Unbilled receivables from commercial and international customers	25,137,000		21,588,000
Receivables from the U.S. government and its agencies	43,241,000		32,870,000
Unbilled receivables from the U.S. government and its agencies	6,101,000		7,018,000
Total accounts receivable	152,030,000		128,585,000
Less allowance for doubtful accounts	2,102,000		1,769,000
Accounts receivable, net	$	149,928,000	126,816,000

Unbilled receivables as of January 31, 2021 relate to contracts-in-progress for which revenue has been recognized, but for which we have not yet earned the right to bill the customer for work performed to-date. Under ASC 606, unbilled receivables constitute contract assets. Management estimates that a substantial portion of the amounts not yet billed at January 31, 2021 will be billed and collected within one year.

Allowance for doubtful accounts as of January 31, 2021 includes $215,000 recorded at August 1, 2020 as a result of our adoption of FASB ASU No. 2016-13, which is discussed in more detail in Note (3) - "Adoption of Accounting Standards and Updates."

As of January 31, 2021, the U.S. government (and its agencies) and Verizon represented 32.5% and 12.7%, respectively, of total accounts receivable. As of July 31, 2020, except for the U.S. government (and its agencies), which represented 31.0% of total accounts receivable, there were no other customers which accounted for greater than 10.0% of total accounts receivable.