Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 5	$ 24	$ 24
Other comprehensive income (loss), net of tax:
Foreign currency adjustment	9	(37)
Deferred gains (losses) on derivative financial instruments	1	(2)
Other comprehensive income (loss), net of tax	10	(39)
Total comprehensive income (loss)	15	(15)
Less: Income attributable to noncontrolling interest	(1)	(2)
Comprehensive income (loss) attributable to Warner Music Group Corp.	$ 14	$ (17)