Revenues - Contract Balances (Details) - USD ($) $ in Millions	Jan. 29, 2021	Jan. 31, 2020
Disaggregation of Revenue [Line Items]
Allowance for doubtful accounts receivable	$ 3	$ 4
Receivables, net
Disaggregation of Revenue [Line Items]
Billed and billable receivables, net	600	720
Contract assets	362	379
Other assets
Disaggregation of Revenue [Line Items]
Contract assets	18	17
Other accrued liabilities
Disaggregation of Revenue [Line Items]
Contract liabilities	82	41
Other long-term liabilities
Disaggregation of Revenue [Line Items]
Contract liabilities	$ 17	$ 10

Amount of allowance for credit loss on accounts receivable.

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