Accounts Receivable

12 Months Ended

Jan. 30, 2021

Accounts Receivable, Contract Assets, and Contract Liabilities

The following provides further details on the balance sheet accounts of accounts receivable, net; contract assets; and contract liabilities. See Note 2, Significant Accounting Policies and Estimates, for further information on our policies related to these balance sheet accounts, as well as our revenue recognition policies.

Accounts Receivable

Accounts receivable, net classified as current, consisted of the following (dollars in thousands):


	January 30, 2021		January 25, 2020
Trade accounts receivable	$	352,501	$	355,805
Unbilled accounts receivable	492,324		453,353
Retainage	14,974		12,669
Total	859,799		821,827
Less: allowance for doubtful accounts	(1,676)		(4,582)
Accounts receivable, net	$	858,123	$	817,245

We maintain an allowance for doubtful accounts for estimated losses on uncollected balances. The allowance for doubtful accounts changed as follows (dollars in thousands):


	January 30, 2021		January 25, 2020
Allowance for doubtful accounts at beginning of period	$	4,582	$	17,702
Cumulative effect from implementation of ASU 2016-13	471		—
Provision for bad debt (recovery)	406		(6,540)
Amounts charged against the allowance	(3,783)		(6,580)
Allowance for doubtful accounts at end of period	$	1,676	$	4,582

Contract Assets and Contract Liabilities

Net contract assets consisted of the following (dollars in thousands):


	January 30, 2021		January 25, 2020
Contract assets	$	197,110	$	253,005
Contract liabilities	14,101		16,332
Contract assets, net	$	183,009	$	236,673

The decrease in contract assets, net, in fiscal 2021 from fiscal 2020 primarily resulted from reduced services performed and increased billings under contracts consisting of multiple tasks. There were no other significant changes in contract assets during the period. During fiscal 2021, we performed services and recognized revenue related to all but an immaterial amount of our contract liabilities that existed at January 25, 2020. See Note 7, Other Current Assets and Other Assets, for information on our long-term contract assets.

Customer Credit Concentration

Customers whose combined amounts of accounts receivable and contract assets, net exceeded 10% of total combined accounts receivable and contract assets, net as of January 30, 2021 or January 25, 2020 were as follows (dollars in millions):


	January 30, 2021				January 25, 2020
	Amount		% of Total		Amount		% of Total
Verizon Communications Inc.	$	389.9	37.4	%	$	440.2	41.8	%
Lumen Technologies (1)	$	173.5	16.6	%	$	175.8	16.7	%
Comcast Corporation	$	131.7	12.6	%	$	114.0	10.8	%

(1) Formerly known as CenturyLink, Inc.

We believe that none of the customers above were experiencing financial difficulties that would materially impact the collectability of our total accounts receivable and contract assets, net, as of January 30, 2021 or January 25, 2020. On April 14, 2020, Frontier Communications filed a voluntary petition under Chapter 11 of the United States Bankruptcy Code in the U.S. Bankruptcy Court for the Southern District of New York, to implement a prearranged debt restructuring plan. As of January 30, 2021, the Company had prepetition outstanding receivables and contract assets in aggregate of approximately $0.6 million with Frontier Communications. The Company has been identified as a critical vendor and expects to continue to provide service to Frontier Communications pursuant to existing contractual obligations and be paid in full for prepetition and post-petition receivables and contract assets.