Segment Information - Schedule of Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 1,045	$ 917
Operating income	90	94
Amortization of intangible assets	53	51
Depreciation of property, plant and equipment	12	12
OIBDA	155	157
Operating Segments | Recorded Music
Segment Reporting Information [Line Items]
Revenues	904	797
Operating income	129	123
Amortization of intangible assets	36	35
Depreciation of property, plant and equipment	8	7
OIBDA	173	165
Operating Segments | Music Publishing
Segment Reporting Information [Line Items]
Revenues	143	124
Operating income	(1)	(2)
Amortization of intangible assets	17	16
Depreciation of property, plant and equipment	1	2
OIBDA	17	16
Corporate Expenses and Eliminations
Segment Reporting Information [Line Items]
Revenues	(2)	(4)
Operating income	(38)	(27)
Depreciation of property, plant and equipment	3	3
OIBDA	$ (35)	$ (24)