Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
Income Taxes [Line Items]
Valuation allowance	$ 1,705	$ 1,567
Undistributed Earnings of Foreign Subsidiaries	4,700
Undistributed earnings of foreign subsidiaries for which deferred taxes have not been provided	1,200
Gross unrecognized tax benefits that would reduce income tax expense and effective tax rate, if recognized	444	469	$ 501
Accrued interest and penalties related to unrecognized tax benefits	234	221	231
Additional accrued interest related to unrecognized tax benefits	43	22	68
Reductions in accrued interest as a result of audit settlements and other prior-year adjustments	30	32	54
Unrecognized tax benefits, reasonably possible reduction due to payments for or resolution of open tax matters	163
Adjustments to Income Tax Expense, Income Tax Benefit from Share-based Compensation	125
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation		207	313
International Theme Parks
Income Taxes [Line Items]
Valuation allowance	1,300	1,200
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Noncontrolling Interest	$ 200	$ 400
Tax Credit Carryforward, Description		indefinite carryforward period in France and Hong Kong and a five-year carryforward period in China
International Theme Parks | CHINA
Income Taxes [Line Items]
Tax Credit Carryforward, Period	5 years
Disneyland Paris
Income Taxes [Line Items]
Deferred Tax Assets, Adjustment			$ 399