Reportable Segments (Schedule of Reconciliation of Adjusted OIBDA to Net Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting [Abstract]
Net income available to Discovery, Inc.	$ 271	$ 947	$ 648	$ 1,331
Net income attributable to redeemable noncontrolling interests	4	4	6	9
Net income attributable to noncontrolling interests	25	36	53	65
Income tax expense (benefit)	156	(271)	286	(118)
Income before income taxes	456	716	993	1,287
Other expense (income), net	6	(9)	64	18
Loss from equity investees, net	23	20	44	9
Loss on extinguishment of debt	71	23	71	28
Interest expense, net	161	161	324	343
Operating income	717	911	1,496	1,685
Restructuring and other charges	7	7	22	12
Impairment of goodwill and other intangible assets	38	0	38	0
Depreciation and amortization	334	320	660	692
Employee share-based compensation	31	39	24	69
Transaction and integration costs	0	4	0	11
Settlement of a withholding tax claim	0	0	0	(29)
Total Adjusted OIBDA	$ 1,127	$ 1,281	$ 2,240	$ 2,440