CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings (Viacom and noncontrolling interests)	$ 334	$ 553
Other comprehensive income/(loss), net of tax:
Foreign currency translation adjustments	(54)	9
Defined benefit pension plans	1	2
Cash flow hedges	2	1
Available-for-sale securities	0	30
Other comprehensive income/(loss) (Viacom and noncontrolling interests)	(51)	42
Comprehensive income	283	595
Less: Comprehensive income attributable to noncontrolling interest	10	16
Comprehensive income attributable to Viacom	$ 273	$ 579

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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