Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Income Taxes [Line Items]
Effective income tax rate reconciliation, at federal statutory income tax rate, percent			21.00%	35.00%
Effective tax rate			37.00%	51.00%	(48.00%)
Income tax expense benefit continuing operations adjustment of deferred tax asset liability	$ 68
Non-cash income tax benefit		$ 37
Income tax benefit recognized				$ 36
Impact of Tax Reform				40
Decreased in unrecognized tax benefits					$ (4)
Impact on income tax expenses due to decrease in unrecognized tax benefits			$ 1		(3)
Unrecognized Tax Benefits	20		20	20	14	$ 18
Net uncertain tax positions, if recognized affect effective tax rate			10
Unrecognized Tax Benefits results from positions if sustained offset by change in valuation allowance			10
Increase related to merger				8
Unrecognized tax benefits, interest and penalty expense					3
Unrecognized tax benefits, accrued interest and penalties			7
CompuCom Systems, Inc
Income Taxes [Line Items]
Increase related to merger				8
Unrecognized tax benefit is currently covered under an indemnification agreement			3
Unrecognized tax benefits, accrued interest and penalties			1
Valuation Allowance of Deferred Tax Assets
Income Taxes [Line Items]
Impact of Tax Reform				40
Reductions			2	41	382
Deferred Income Taxes and Other Long-Term Liabilities
Income Taxes [Line Items]
Deferred income tax liabilities	$ 21		20	21
U.S. Federal and State
Income Taxes [Line Items]
Estimated valuation allowance, determined to be reduced				$ 40	$ 382
Non-cash income tax benefit		$ 37
Operating Loss Carry forwards			106
Alternate minimum tax credit carryforwards			$ 89
U.S. Federal and State | Minimum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2020
U.S. Federal and State | Maximum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2033
U.S. Federal and State | Expire in 2019
Income Taxes [Line Items]
Operating Loss Carry forwards			$ 0
U.S. Federal and State | Capital loss carryover
Income Taxes [Line Items]
Capital loss carryover, amount to offset future capital gains			$ 609
Capital loss carryover, expiration year			2022
U.S. Federal and State | Capital loss carryover | Minimum
Income Taxes [Line Items]
Capital loss carryover, expiration year			2021
U.S. Federal and State | Capital loss carryover | Maximum
Income Taxes [Line Items]
Capital loss carryover, expiration year			2023
Foreign
Income Taxes [Line Items]
Operating Loss Carry forwards			$ 102
Foreign | Minimum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2020
Foreign | Maximum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2038
Foreign | Expire in 2019
Income Taxes [Line Items]
Operating Loss Carry forwards			$ 0
Foreign | Indefinite Carryforward
Income Taxes [Line Items]
Operating Loss Carry forwards			47
State
Income Taxes [Line Items]
Operating Loss Carry forwards			1,200
Capital loss carryover, amount to offset future capital gains			$ 548
Capital loss carryover, expiration year			2022
State | Minimum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2020
Capital loss carryover, expiration year			2021
State | Maximum
Income Taxes [Line Items]
Operating loss carryforwards, expiration dates			2038
Capital loss carryover, expiration year			2023
State | Expire in 2019
Income Taxes [Line Items]
Operating Loss Carry forwards			$ 23
U.S. Federal Foreign
Income Taxes [Line Items]
Capital loss carryover, amount to offset future capital gains			$ 125
U.S. Federal Foreign | Earliest Tax Year
Income Taxes [Line Items]
Capital loss carryover, expiration year			2019
U.S. Federal Foreign | Latest Tax Year
Income Taxes [Line Items]
Capital loss carryover, expiration year			2028
State and Foreign
Income Taxes [Line Items]
Capital loss carryover, amount to offset future capital gains			$ 14
State and Foreign | Indefinite Carryforward
Income Taxes [Line Items]
Capital loss carryover, amount to offset future capital gains			$ 2
State and Foreign | Earliest Tax Year
Income Taxes [Line Items]
Capital loss carryover, expiration year			2023
State and Foreign | Latest Tax Year
Income Taxes [Line Items]
Capital loss carryover, expiration year			2028