Income Taxes (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended				6 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2018	Dec. 22, 2017	Mar. 30, 2018	Dec. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 29, 2018	Mar. 30, 2018	Mar. 31, 2017	Jun. 29, 2018
Income Tax Contingency [Line Items]
Statutory tax rate		35.00%
Estimated write-down to deferred tax assets balance due to changes in enacted tax rate			$ (19)	$ (52)
Estimated write-down to deferred tax asset balance per diluted share (in dollars per share)			$ 0.15	$ 0.43
Provisional income tax benefit from the impact of lower corporate tax rates in estimated annual rate for fiscal year				$ 26
Provisional income tax benefit from the impact of lower corporate tax rates in estimated annual rate for fiscal year, per diluted share (in dollars per share)				$ 0.21
Income tax benefit recorded due to change in estimated write-down of net deferred tax asset balance			$ 33
Income tax benefit recorded due to change in estimated write-down of net deferred tax asset balance per diluted share (in dollars per share)			$ 0.27
Effective tax rate			5.60%			29.60%		24.60%	29.70%
Benefit from favorable impact of releasing uncertain tax positions and excess tax benefits related to equity-based compensation								$ 22
Benefit from favorable impact of releasing uncertain tax positions and excess tax benefits related to equity-based compensation, per diluted share (in dollars per share)								$ 0.18
Deferred tax liability for netted foreign E&P			$ 25					$ 25
Increase in deferred tax liability due to potential cumulative basis differences in netted foreign E&P			116					116
Pension
Income Tax Contingency [Line Items]
Defined benefit plan, voluntary contributions by employer during period			301					301
U.S. | Pension
Income Tax Contingency [Line Items]
Defined benefit plan, voluntary contributions by employer during period			$ 300		$ 400	$ 40		$ 300	$ 143
Scenario, Forecast
Income Tax Contingency [Line Items]
Statutory tax rate							21.00%			28.00%
Effective tax rate at which deferred tax assets and liabilities will be reversed after fiscal year	21.00%