Amount due from customers or clients, more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Supplemental Cash Flow and Other Information Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017
Accounts Receivable [Abstract]
Accounts Receivable, Net, Noncurrent	$ 493		$ 493		$ 486
Acquisitions [Abstract]
Purchase Price Allocation			70
Investments [Abstract]
Cost-method Investments, Other than Temporary Impairment		$ 10	46	$ 10
Proceeds from sale of EPIX		593	0	593
Gain on sale of EPIX	0	$ 285	0	$ 285
Variable Interest Entities [Abstract]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	154		154		159
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	$ 6		$ 6		$ 8
Viacom18 [Member]
Equity Method Investment, Percentage Sold			1.00%
Proceeds from Sale of Equity Method Investments			$ 20
Equity Method Investment, Realized Gain (Loss) on Disposal			$ 16
EPIX [Member]
Equity Method Investment, Percentage Sold		49.76%		49.76%
Transaction Costs Disposal Of Equity Method Investment		$ 4		$ 4
Proceeds from Equity Method Investment, Distribution		$ 37		$ 37