Restructuring Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring Charges and Programming Inventory Restructure, Net of Tax	$ 148
Restructuring and Related Costs	71
Programming inventory restructure	77
Restructuring Reserve	172	$ 195
Restructuring Reserve, Period Increase (Decrease)	40
Restructuring Reserve Settled with Cash Severance	63
Restructuring Reserve, Current	124
Restructuring Reserve, Noncurrent	48
Restructuring Reserve Settled with Cash Exit Costs	6
Allocated Share-Based Compensation Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 1

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Amount of increase (decrease) in the accrual for restructuring costs.

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Amounts charged against earnings in the period for programming inventory restructuring associated with restructuring pursuant to a duly authorized plan.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan and amounts charged against earnings in the period for programming inventory restructuring associated with restructuring pursuant to a duly authorized plan, net of tax. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of cash paid in the period related to exit costs.

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Amount of cash paid in the period related to employee severance.

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Expenses incurred for severance, exit activities and other related costs pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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