Guarantor and Non-Guarantor Subsidiaries Financial Information - Consolidating Statement of Cash Flows (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities
Net income (loss)	$ 24	$ 28
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	63	75
Unrealized (gains)/losses and remeasurement of foreign denominated loans	(17)	(8)
Deferred income taxes	(2)	(9)
Loss on extinguishment of debt	32
Non-cash interest expense	3	2
Non-cash stock-based compensation expenses	10	1
Changes in operating assets and liabilities:
Accounts receivable	(65)	(63)
Inventories	3	(1)
Royalty advances	1	(16)
Accounts payable and accrued liabilities	(12)	(11)
Royalty payables	112	58
Accrued interest	(10)	(11)
Deferred revenue	(1)	1
Other balance sheet changes	15	15
Net cash provided by operating activities	156	61
Cash flows from investing activities
Acquisition of music publishing rights, net	(1)	(7)
Capital expenditures	(8)	(10)
Investments and acquisitions of businesses, net	(3)	(1)
Net cash used in investing activities	(12)	(18)
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp. Senior Term Loan Facility	22
Financing costs paid	(27)
Deferred financing costs paid	(12)
Repayment of Acquisition Corp. Senior Term Loan Facility		(3)
Distribution to noncontrolling interest holder		(3)
Net cash used in financing activities	(38)	(6)
Effect of exchange rate changes on cash and equivalents	(10)	(5)
Net increase (decrease) in cash and equivalents	96	32
Cash and equivalents at beginning of period	359	246
Cash and equivalents at end of period	455	278
4.125% Senior Secured Notes
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	380
4.875% Senior Secured Notes
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	250
6.00% Senior Secured Notes
Cash flows from financing activities
Repayment of Senior Secured Notes	(450)
6.25% Senior Secured Notes
Cash flows from financing activities
Repayment of Senior Secured Notes	(173)
5.625% Senior Secured Notes
Cash flows from financing activities
Repayment of Senior Secured Notes	(28)
Reportable Legal Entities | WMG Acquisition Corp.
Cash flows from operating activities
Net income (loss)	22	32
Adjustments to reconcile net income to net cash provided by operating activities:
Unrealized (gains)/losses and remeasurement of foreign denominated loans	(21)	120
Loss on extinguishment of debt	32
Non-cash interest expense	3	2
Equity (gains) losses, including distributions	(83)	(47)
Changes in operating assets and liabilities:
Accrued interest	(10)	(6)
Net cash provided by operating activities	(57)	101
Cash flows from investing activities
Advances to issuer	95	(88)
Net cash used in investing activities	95	(88)
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp. Senior Term Loan Facility	22
Financing costs paid	(27)
Deferred financing costs paid	(12)
Repayment of Acquisition Corp. Senior Term Loan Facility		(3)
Net cash used in financing activities	(38)	(13)
Dividend by Acquisition Corp. to Holdings Corp.		(10)
Reportable Legal Entities | Guarantor Subsidiaries
Cash flows from operating activities
Net income (loss)	95	73
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	35	41
Unrealized (gains)/losses and remeasurement of foreign denominated loans	(9)	19
Non-cash stock-based compensation expenses	10	1
Equity (gains) losses, including distributions	(40)	(19)
Changes in operating assets and liabilities:
Accounts receivable	(19)	(5)
Inventories	2	2
Royalty advances	7	(3)
Accounts payable and accrued liabilities	6	(184)
Royalty payables	40	7
Deferred revenue	(33)	(2)
Other balance sheet changes	12
Net cash provided by operating activities	106	(70)
Cash flows from investing activities
Acquisition of music publishing rights, net		(6)
Capital expenditures	(6)	(7)
Investments and acquisitions of businesses, net	(3)	(1)
Proceeds from divestiture of asset	4
Net cash used in investing activities	(9)	(14)
Cash flows from financing activities
Change in due to (from) issuer	(95)	88
Net cash used in financing activities	(95)	88
Net increase (decrease) in cash and equivalents	2	4
Cash and equivalents at beginning of period	180	73
Cash and equivalents at end of period	182	77
Reportable Legal Entities | Non-Guarantor Subsidiaries
Cash flows from operating activities
Net income (loss)	3	(6)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	28	34
Unrealized (gains)/losses and remeasurement of foreign denominated loans	13	(147)
Deferred income taxes	(2)	(9)
Changes in operating assets and liabilities:
Accounts receivable	(46)	(58)
Inventories	1	(3)
Royalty advances	(6)	(13)
Accounts payable and accrued liabilities	9	173
Royalty payables	72	51
Deferred revenue	32	3
Other balance sheet changes	3	15
Net cash provided by operating activities	107	40
Cash flows from investing activities
Acquisition of music publishing rights, net	(1)	(1)
Capital expenditures	(2)	(3)
Net cash used in investing activities	(3)	(4)
Cash flows from financing activities
Distribution to noncontrolling interest holder		(3)
Net cash used in financing activities		(3)
Effect of exchange rate changes on cash and equivalents	(10)	(5)
Net increase (decrease) in cash and equivalents	94	28
Cash and equivalents at beginning of period	179	173
Cash and equivalents at end of period	273	201
Reportable Legal Entities | WMG Acquisition Corp. Consolidated
Cash flows from operating activities
Net income (loss)	24	33
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	63	75
Unrealized (gains)/losses and remeasurement of foreign denominated loans	(17)	(8)
Deferred income taxes	(2)	(9)
Loss on extinguishment of debt	32
Non-cash interest expense	3	2
Non-cash stock-based compensation expenses	10	1
Changes in operating assets and liabilities:
Accounts receivable	(65)	(63)
Inventories	3	(1)
Royalty advances	1	(16)
Accounts payable and accrued liabilities	(12)	(11)
Royalty payables	112	58
Accrued interest	(10)	(6)
Deferred revenue	(1)	1
Other balance sheet changes	15	15
Net cash provided by operating activities	156	71
Cash flows from investing activities
Acquisition of music publishing rights, net	(1)	(7)
Capital expenditures	(8)	(10)
Investments and acquisitions of businesses, net	(3)	(1)
Net cash used in investing activities	(12)	(18)
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp. Senior Term Loan Facility	22
Financing costs paid	(27)
Deferred financing costs paid	(12)
Repayment of Acquisition Corp. Senior Term Loan Facility		(3)
Distribution to noncontrolling interest holder		(3)
Net cash used in financing activities	(38)	(16)
Dividend by Acquisition Corp. to Holdings Corp.		(10)
Effect of exchange rate changes on cash and equivalents	(10)	(5)
Net increase (decrease) in cash and equivalents	96	32
Cash and equivalents at beginning of period	359	246
Cash and equivalents at end of period	455	278
Reportable Legal Entities | WMG Holdings Corp.
Cash flows from operating activities
Net income (loss)	22	27
Adjustments to reconcile net income to net cash provided by operating activities:
Equity (gains) losses, including distributions	(22)	(32)
Changes in operating assets and liabilities:
Accrued interest		(5)
Net cash provided by operating activities		(10)
Cash flows from financing activities
Net cash used in financing activities		10
Dividend by Acquisition Corp. to Holdings Corp.		10
Reportable Legal Entities | Warner Music Group Corp.
Cash flows from operating activities
Net income (loss)	22	27
Adjustments to reconcile net income to net cash provided by operating activities:
Equity (gains) losses, including distributions	(22)	(27)
Reportable Legal Entities | 4.125% Senior Secured Notes | WMG Acquisition Corp.
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	380
Reportable Legal Entities | 4.125% Senior Secured Notes | WMG Acquisition Corp. Consolidated
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	380
Reportable Legal Entities | 4.875% Senior Secured Notes | WMG Acquisition Corp.
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	250
Reportable Legal Entities | 4.875% Senior Secured Notes | WMG Acquisition Corp. Consolidated
Cash flows from financing activities
Proceeds from issuance of Acquisition Corp	250
Reportable Legal Entities | 6.00% Senior Secured Notes | WMG Acquisition Corp.
Cash flows from financing activities
Repayment of Senior Secured Notes	(450)
Reportable Legal Entities | 6.00% Senior Secured Notes | WMG Acquisition Corp. Consolidated
Cash flows from financing activities
Repayment of Senior Secured Notes	(450)
Reportable Legal Entities | 6.25% Senior Secured Notes | WMG Acquisition Corp.
Cash flows from financing activities
Repayment of Senior Secured Notes	(173)
Reportable Legal Entities | 6.25% Senior Secured Notes | WMG Acquisition Corp. Consolidated
Cash flows from financing activities
Repayment of Senior Secured Notes	(173)
Reportable Legal Entities | 5.625% Senior Secured Notes | WMG Acquisition Corp.
Cash flows from financing activities
Repayment of Senior Secured Notes	(28)
Reportable Legal Entities | 5.625% Senior Secured Notes | WMG Acquisition Corp. Consolidated
Cash flows from financing activities
Repayment of Senior Secured Notes	(28)
Eliminations
Cash flows from operating activities
Net income (loss)	(44)	(59)
Adjustments to reconcile net income to net cash provided by operating activities:
Equity (gains) losses, including distributions	44	59
Eliminations | WMG Acquisition Corp.
Cash flows from operating activities
Net income (loss)	(96)	(66)
Adjustments to reconcile net income to net cash provided by operating activities:
Equity (gains) losses, including distributions	123	66
Changes in operating assets and liabilities:
Accounts payable and accrued liabilities	(27)
Cash flows from investing activities
Advances to issuer	(95)	88
Net cash used in investing activities	(95)	88
Cash flows from financing activities
Change in due to (from) issuer	95	(88)
Net cash used in financing activities	$ 95	$ (88)