Guarantor and Non-Guarantor Subsidiaries Financial Information - Consolidating Statement of Cash Flows (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net (loss) income	$ (41)	$ (36)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	79	78
Unrealized gains/losses and remeasurement of foreign denominated loans	14	(20)
Deferred income taxes	0	(16)
Non-cash interest expense	2	4
Non-cash share-based compensation expense	0	3
Equity losses (gains), including distributions	0	0
Changes in operating assets and liabilities:
Accounts receivable	(67)	(56)
Inventories	(1)	(1)
Royalty advances	(7)	(35)
Accounts payable and accrued liabilities	(47)	(79)
Royalty payables	46	56
Accrued interest	(12)	(17)
Deferred revenue	39	60
Other balance sheet changes	30	7
Net cash provided by (used in) operating activities	35	(52)
Cash flows from investing activities
Acquisition of music publishing rights, net	(5)	(10)
Capital expenditures	(24)	(12)
Investments and acquisitions of businesses, net	(8)	(4)
Advances to issuer	0	0
Net cash used in investing activities	(37)	(26)
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	100	155
Repayment of the Revolving Credit Facility	(100)	(100)
Repayment of Acquisition Corp. Senior Term Loan Facility	(3)	0
Distribution to noncontrolling interest holder	0	(1)
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	(3)	54
Effect of exchange rate changes on cash and equivalents	(7)	(2)
Net decrease in cash and equivalents	(12)	(26)
Cash and equivalents at beginning of period	157	155
Cash and equivalents at end of period	145	129
Eliminations
Cash flows from operating activities
Net (loss) income	17	13
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	0	0
Unrealized gains/losses and remeasurement of foreign denominated loans	0	0
Deferred income taxes	0	0
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	(8)	(16)
Changes in operating assets and liabilities:
Accounts receivable	0	0
Inventories	0	0
Royalty advances	0	0
Accounts payable and accrued liabilities	0	(21)
Royalty payables	0	0
Accrued interest	0	0
Deferred revenue	0	0
Other balance sheet changes	(9)	24
Net cash provided by (used in) operating activities	0	0
Cash flows from investing activities
Acquisition of music publishing rights, net	0	0
Capital expenditures	0	0
Investments and acquisitions of businesses, net	0	0
Advances to issuer	(59)	29
Net cash used in investing activities	(59)	29
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	59	(29)
Net cash (used in) provided by financing activities	59	(29)
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	0	0
Cash and equivalents at beginning of period	0	0
Cash and equivalents at end of period	0	0
Eliminations
Cash flows from operating activities
Net (loss) income	79	69
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	0	0
Unrealized gains/losses and remeasurement of foreign denominated loans	0	0
Deferred income taxes	0	0
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	(79)	(69)
Changes in operating assets and liabilities:
Accounts receivable	0	0
Inventories	0	0
Royalty advances	0	0
Accounts payable and accrued liabilities	0	0
Royalty payables	0	0
Accrued interest	0	0
Deferred revenue	0	0
Other balance sheet changes	0	0
Net cash provided by (used in) operating activities	0	0
Cash flows from investing activities
Acquisition of music publishing rights, net	0	0
Capital expenditures	0	0
Investments and acquisitions of businesses, net	0	0
Advances to issuer	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	0	0
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	0	0
Cash and equivalents at beginning of period	0	0
Cash and equivalents at end of period	0	0
WMG Acquisition Corp. (issuer)
Cash flows from operating activities
Net (loss) income	(37)	(32)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	0	0
Unrealized gains/losses and remeasurement of foreign denominated loans	(9)	3
Deferred income taxes	0	0
Non-cash interest expense	2	4
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	6	21
Changes in operating assets and liabilities:
Accounts receivable	0	0
Inventories	0	0
Royalty advances	0	0
Accounts payable and accrued liabilities	0	0
Royalty payables	0	0
Accrued interest	(7)	(12)
Deferred revenue	0	0
Other balance sheet changes	(1)	0
Net cash provided by (used in) operating activities	(46)	(16)
Cash flows from investing activities
Acquisition of music publishing rights, net	0	0
Capital expenditures	0	0
Investments and acquisitions of businesses, net	0	0
Advances to issuer	59	(29)
Net cash used in investing activities	59	(29)
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	(10)	(10)
Proceeds from the Revolving Credit Facility	100	155
Repayment of the Revolving Credit Facility	(100)	(100)
Repayment of Acquisition Corp. Senior Term Loan Facility	(3)
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	(13)	45
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	0	0
Cash and equivalents at beginning of period	0	0
Cash and equivalents at end of period	0	0
Guarantor Subsidiaries
Cash flows from operating activities
Net (loss) income	23	44
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	41	38
Unrealized gains/losses and remeasurement of foreign denominated loans	0	(8)
Deferred income taxes	0	0
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	3
Equity losses (gains), including distributions	2	(5)
Changes in operating assets and liabilities:
Accounts receivable	38	2
Inventories	1	1
Royalty advances	2	2
Accounts payable and accrued liabilities	(10)	(109)
Royalty payables	(37)	(56)
Accrued interest	0	0
Deferred revenue	19	60
Other balance sheet changes	4	9
Net cash provided by (used in) operating activities	83	(19)
Cash flows from investing activities
Acquisition of music publishing rights, net	(4)	(6)
Capital expenditures	(18)	(9)
Investments and acquisitions of businesses, net	(6)	(1)
Advances to issuer	0	0
Net cash used in investing activities	(28)	(16)
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	(59)	29
Net cash (used in) provided by financing activities	(59)	29
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	(4)	(6)
Cash and equivalents at beginning of period	26	16
Cash and equivalents at end of period	22	10
Non-Guarantor Subsidiaries
Cash flows from operating activities
Net (loss) income	(39)	(56)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	38	40
Unrealized gains/losses and remeasurement of foreign denominated loans	23	(15)
Deferred income taxes	0	(16)
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	0	0
Changes in operating assets and liabilities:
Accounts receivable	(105)	(58)
Inventories	(2)	(2)
Royalty advances	(9)	(37)
Accounts payable and accrued liabilities	(37)	51
Royalty payables	83	112
Accrued interest	0	0
Deferred revenue	20	0
Other balance sheet changes	36	(26)
Net cash provided by (used in) operating activities	8	(7)
Cash flows from investing activities
Acquisition of music publishing rights, net	(1)	(4)
Capital expenditures	(6)	(3)
Investments and acquisitions of businesses, net	(2)	(3)
Advances to issuer	0	0
Net cash used in investing activities	(9)	(10)
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	(1)
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	0	(1)
Effect of exchange rate changes on cash and equivalents	(7)	(2)
Net decrease in cash and equivalents	(8)	(20)
Cash and equivalents at beginning of period	131	139
Cash and equivalents at end of period	123	119
WMG Acquisition Corp. Consolidated
Cash flows from operating activities
Net (loss) income	(36)	(31)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	79	78
Unrealized gains/losses and remeasurement of foreign denominated loans	14	(20)
Deferred income taxes	0	(16)
Non-cash interest expense	2	4
Non-cash share-based compensation expense	0	3
Equity losses (gains), including distributions	0	0
Changes in operating assets and liabilities:
Accounts receivable	(67)	(56)
Inventories	(1)	(1)
Royalty advances	(7)	(35)
Accounts payable and accrued liabilities	(47)	(79)
Royalty payables	46	56
Accrued interest	(7)	(12)
Deferred revenue	39	60
Other balance sheet changes	30	7
Net cash provided by (used in) operating activities	45	(42)
Cash flows from investing activities
Acquisition of music publishing rights, net	(5)	(10)
Capital expenditures	(24)	(12)
Investments and acquisitions of businesses, net	(8)	(4)
Advances to issuer	0	0
Net cash used in investing activities	(37)	(26)
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	(10)	(10)
Proceeds from the Revolving Credit Facility	100	155
Repayment of the Revolving Credit Facility	(100)	(100)
Repayment of Acquisition Corp. Senior Term Loan Facility	(3)
Distribution to noncontrolling interest holder	0	(1)
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	(13)	44
Effect of exchange rate changes on cash and equivalents	(7)	(2)
Net decrease in cash and equivalents	(12)	(26)
Cash and equivalents at beginning of period	157	155
Cash and equivalents at end of period	145	129
WMG Holdings Corp. (issuer)
Cash flows from operating activities
Net (loss) income	(42)	(37)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	0	0
Unrealized gains/losses and remeasurement of foreign denominated loans	0	0
Deferred income taxes	0	0
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	37	32
Changes in operating assets and liabilities:
Accounts receivable	0	0
Inventories	0	0
Royalty advances	0	0
Accounts payable and accrued liabilities	0	0
Royalty payables	0	0
Accrued interest	(5)	(5)
Deferred revenue	0	0
Other balance sheet changes	0	0
Net cash provided by (used in) operating activities	(10)	(10)
Cash flows from investing activities
Acquisition of music publishing rights, net	0	0
Capital expenditures	0	0
Investments and acquisitions of businesses, net	0	0
Advances to issuer	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	10	10
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	10	10
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	0	0
Cash and equivalents at beginning of period	0	0
Cash and equivalents at end of period	0	0
Warner Music Group Corp.
Cash flows from operating activities
Net (loss) income	(42)	(37)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	0	0
Unrealized gains/losses and remeasurement of foreign denominated loans	0	0
Deferred income taxes	0	0
Non-cash interest expense	0	0
Non-cash share-based compensation expense	0	0
Equity losses (gains), including distributions	42	37
Changes in operating assets and liabilities:
Accounts receivable	0	0
Inventories	0	0
Royalty advances	0	0
Accounts payable and accrued liabilities	0	0
Royalty payables	0	0
Accrued interest	0	0
Deferred revenue	0	0
Other balance sheet changes	0	0
Net cash provided by (used in) operating activities	0	0
Cash flows from investing activities
Acquisition of music publishing rights, net	0	0
Capital expenditures	0	0
Investments and acquisitions of businesses, net	0	0
Advances to issuer	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Dividend by Acquisition Corp. to Holdings Corp.	0	0
Proceeds from the Revolving Credit Facility	0	0
Repayment of the Revolving Credit Facility	0	0
Repayment of Acquisition Corp. Senior Term Loan Facility	0
Distribution to noncontrolling interest holder	0	0
Change in due to (from) issuer	0	0
Net cash (used in) provided by financing activities	0	0
Effect of exchange rate changes on cash and equivalents	0	0
Net decrease in cash and equivalents	0	0
Cash and equivalents at beginning of period	0	0
Cash and equivalents at end of period	$ 0	$ 0