Warner Bros. Discovery (WBD) 10-K 28 Feb 18 2017 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2017	Feb. 21, 2018	Jun. 30, 2017
Entity Registrant Name	Discovery Communications, Inc.
Entity Central Index Key	1,437,107
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 9
Series A Common Stock [Member]
Entity Common Stock, Shares Outstanding		155,613,008
Series B Common Stock [Member]
Entity Common Stock, Shares Outstanding		6,512,379
Series C Common Stock [Member]
Entity Common Stock, Shares Outstanding		219,782,537

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 7,309,000,000	$ 300,000,000
Receivables, net	1,838,000,000	1,495,000,000
Content rights, net	410,000,000	310,000,000
Deferred income taxes		0
Prepaid expenses and other current assets	434,000,000	397,000,000
Total current assets	9,991,000,000	2,502,000,000
Noncurrent content rights, net	2,213,000,000	2,089,000,000
Property and equipment, net	597,000,000	482,000,000
Goodwill	7,073,000,000	8,040,000,000
Intangible assets, net	1,770,000,000	1,512,000,000
Equity method investments, including note receivable	335,000,000	557,000,000
Other noncurrent assets	576,000,000	490,000,000
Total assets	22,555,000,000	15,672,000,000
Current liabilities:
Accounts payable	277,000,000	241,000,000
Accrued liabilities	1,309,000,000	1,075,000,000
Deferred revenues	255,000,000	163,000,000
Current portion of debt	30,000,000	82,000,000
Total current liabilities	1,871,000,000	1,561,000,000
Noncurrent portion of debt	14,755,000,000	7,841,000,000
Deferred income taxes	319,000,000	467,000,000
Other noncurrent liabilities	587,000,000	393,000,000
Total liabilities	17,532,000,000	10,262,000,000
Commitments and contingencies (See Note 20)
Redeemable noncontrolling interests	413,000,000	243,000,000
Discovery Communications, Inc. stockholders' equity
Additional paid-in capital	7,295,000,000	7,046,000,000
Treasury stock, at cost	(6,737,000,000)	(6,356,000,000)
Retained earnings	4,632,000,000	5,232,000,000
Accumulated other comprehensive loss	(585,000,000)	(762,000,000)
Total equity	4,610,000,000	5,167,000,000
Total liabilities and equity	22,555,000,000	15,672,000,000
Series A Convertible Preferred Stock [Member]
Discovery Communications, Inc. stockholders' equity
Convertible preferred stock	0	1,000,000
Series C Convertible Preferred Stock [Member]
Discovery Communications, Inc. stockholders' equity
Convertible preferred stock	0	1,000,000
Additional paid-in capital	0
Series A Common Stock [Member]
Discovery Communications, Inc. stockholders' equity
Common stock	1,000,000	1,000,000
Treasury stock, at cost	(171,000,000)
Series B Common Stock [Member]
Discovery Communications, Inc. stockholders' equity
Convertible common stock	0	0
Series C Common Stock [Member]
Discovery Communications, Inc. stockholders' equity
Common stock	4,000,000	$ 4,000,000
Treasury stock, at cost	$ (6,600,000,000)

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Series A-1 Preferred Stock [Member]
Convertible preferred stock, par value (in dollars per share)	$ 0.01
Stock authorized (in shares)	8,000,000
Preferred stock authorized (in shares)	8,000,000
Preferred stock issued (in shares)	8,000,000
Series A Convertible Preferred Stock [Member]
Convertible preferred stock, par value (in dollars per share)		$ 0.01
Preferred stock authorized (in shares)		75,000,000
Preferred stock issued (in shares)		71,000,000
Series C-1 Preferred Stock [Member] [Domain]
Convertible preferred stock, par value (in dollars per share)	$ 0.01
Stock authorized (in shares)	6,000,000
Preferred stock authorized (in shares)	6,000,000
Preferred stock issued (in shares)	6,000,000
Series C Convertible Preferred Stock [Member]
Convertible preferred stock, par value (in dollars per share)		$ 0.01
Stock authorized (in shares)	75,000,000
Preferred stock authorized (in shares)		75,000,000
Preferred stock issued (in shares)		28,000,000
Series A Common Stock [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,700,000,000	1,700,000,000
Common stock issued (in shares)	157,000,000	155,000,000
Series B Common Stock [Member]
Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Stock authorized (in shares)	100,000,000	100,000,000
Stock issued (in shares)	7,000,000	7,000,000
Series C Common Stock [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	2,000,000,000	2,000,000,000
Common stock issued (in shares)	383,000,000	381,000,000

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Distribution	$ 3,474,000,000	$ 3,213,000,000	$ 3,068,000,000
Advertising	3,073,000,000	2,970,000,000	3,004,000,000
Other	326,000,000	314,000,000	322,000,000
Total revenues	6,873,000,000	6,497,000,000	6,394,000,000
Costs and expenses:
Costs of revenues, excluding depreciation and amortization	2,656,000,000	2,432,000,000	2,343,000,000
Selling, general and administrative	1,768,000,000	1,690,000,000	1,669,000,000
Impairment of goodwill	1,327,000,000	0	0
Depreciation and amortization	330,000,000	322,000,000	330,000,000
Restructuring and other charges	75,000,000	58,000,000	50,000,000
Loss (gain) on disposition	4,000,000	(63,000,000)	17,000,000
Total costs and expenses	6,160,000,000	4,439,000,000	4,409,000,000
Operating income	713,000,000	2,058,000,000	1,985,000,000
Interest expense	(475,000,000)	(353,000,000)	(330,000,000)
Loss on extinguishment of debt	(54,000,000)	0	0
(Loss) income from equity investees, net	(211,000,000)	(38,000,000)	1,000,000
Other (expense) income, net	(110,000,000)	4,000,000	(97,000,000)
Income before income taxes	(137,000,000)	1,671,000,000	1,559,000,000
Income taxes	(176,000,000)	(453,000,000)	(511,000,000)
Net income	(313,000,000)	1,218,000,000	1,048,000,000
Net income attributable to noncontrolling interests	0	(1,000,000)	(1,000,000)
Net income attributable to redeemable noncontrolling interests	(24,000,000)	(23,000,000)	(13,000,000)
Net income attributable to Discovery Communications, Inc.	$ (337,000,000)	$ 1,194,000,000	$ 1,034,000,000
Series A, B and C Common Stock [Member]
Net (loss) income per share available to Discovery Communications, Inc. Series A, B and C common stockholders:
Basic (in dollars per share)	$ (0.59)	$ 1.97	$ 1.59
Diluted (in dollars per share)	$ (0.59)	$ 1.96	$ 1.58
Weighted average shares outstanding:
Basic (in shares)	384	401	432
Diluted (in shares)	576	610	656

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities
Net income	$ (313,000,000)	$ 1,218,000,000	$ 1,048,000,000
Adjustments to reconcile net (loss) income to cash provided by operating activities:
Equity-based compensation expense	39,000,000	69,000,000	35,000,000
Depreciation and amortization	330,000,000	322,000,000	330,000,000
Content amortization and impairment expense	1,910,000,000	1,773,000,000	1,709,000,000
Impairment of goodwill	1,327,000,000	0	0
(Gain) loss on disposition	4,000,000	(63,000,000)	17,000,000
Remeasurement gain on previously held equity interests	(34,000,000)	0	(2,000,000)
Equity in losses of investee companies, net of cash distributions	223,000,000	44,000,000	8,000,000
Deferred income taxes	(199,000,000)	(27,000,000)	2,000,000
Loss on extinguishment of debt	54,000,000	0	0
Realized loss from derivative instruments	98,000,000	3,000,000	5,000,000
Other-than-temporary impairment of AFS investments	0	62,000,000	0
Other, net	85,000,000	50,000,000	35,000,000
Changes in operating assets and liabilities, net of acquisitions and dispositions:
Receivables, net	(258,000,000)	(25,000,000)	(44,000,000)
Content rights, net	(1,947,000,000)	(1,904,000,000)	(1,773,000,000)
Accounts payable and accrued liabilities	265,000,000	(10,000,000)	(2,000,000)
Income taxes receivable and prepaid income taxes	20,000,000	(31,000,000)	(64,000,000)
Other, net	25,000,000	(101,000,000)	(10,000,000)
Cash provided by operating activities	1,629,000,000	1,380,000,000	1,294,000,000
Investing Activities
Payments for (Proceeds from) Investments	444,000,000	272,000,000
Payments for investments, net			(272,000,000)
Purchases of property and equipment	(135,000,000)	(88,000,000)	(103,000,000)
Distributions from equity method investees, net	77,000,000	87,000,000	87,000,000
Proceeds from dispositions, net of cash disposed	29,000,000	19,000,000	61,000,000
Payments for derivative instruments, net	(101,000,000)	0	(9,000,000)
Business acquisitions, net of cash acquired	(60,000,000)	0	(80,000,000)
Other investing activities, net	1,000,000	(2,000,000)	15,000,000
Cash used in investing activities	(633,000,000)	(256,000,000)	(301,000,000)
Financing Activities
Commercial paper (repayments) borrowings, net	(48,000,000)	(45,000,000)	(136,000,000)
Borrowings under revolving credit facility	350,000,000	613,000,000	1,016,000,000
Principal repayments of revolving credit facility	(475,000,000)	(835,000,000)	(265,000,000)
Borrowings from debt, net of discount	7,488,000,000	498,000,000	936,000,000
Principal repayments of debt	(650,000,000)	0	(854,000,000)
Payments of Financing Costs	(40,000,000)	0	0
Principal repayments of capital lease obligations	(33,000,000)	(28,000,000)	(27,000,000)
Repurchases of stock and stock settlements of common stock repurchase contracts	(603,000,000)	(1,374,000,000)	(951,000,000)
Cash proceeds from settlement of common stock repurchase contract	58,000,000	(57,000,000)
Prepayments for outstanding common stock repurchase contracts			0
Purchase of redeemable noncontrolling interests	0	0	(548,000,000)
Payments to redeemable noncontrolling interests	(30,000,000)	(22,000,000)	(42,000,000)
Equity-based plan proceeds, net	16,000,000	39,000,000	(6,000,000)
Hedge of borrowings from debt instruments	0	40,000,000	(29,000,000)
Other financing activities, net	(82,000,000)	(13,000,000)	(13,000,000)
Cash used in financing activities	5,951,000,000	(1,184,000,000)	(919,000,000)
Effect of exchange rate changes on cash and cash equivalents	62,000,000	(30,000,000)	(51,000,000)
Net change in cash and cash equivalents	7,009,000,000	(90,000,000)	23,000,000
Cash and cash equivalents, beginning of period	300,000,000	390,000,000	367,000,000
Cash and cash equivalents, end of period	$ 7,309,000,000	$ 300,000,000	$ 390,000,000

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ (1,137)	$ 223	$ 380	$ 221	$ 309	$ 225	$ 415	$ 269	$ (313)	$ 1,218	$ 1,048
Other comprehensive (loss) income, net of tax
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(135)	1,089	821
Comprehensive income attributable to noncontrolling interests									0	(1)	(1)
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(25)	(23)	10
Comprehensive income attributable to Discovery Communications Inc.									$ (160)	$ 1,065	$ 830

Consolidated Statements Of Equi

Consolidated Statements Of Equity - USD ($) shares in Millions, $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss)/Income [Member]	Discovery Communications, Inc. Stockholders' Equity [Member]	Noncontrolling Interests [Member]	Advance Newhouse [Member]Preferred Stock [Member]	Advance Newhouse [Member]Common Stock [Member]
Beginning Balance (in shares) at Dec. 31, 2014		113
Beginning Balance (in shares) at Dec. 31, 2014			533
Beginning Balance at Dec. 31, 2014	$ 5,604	$ 2	$ 5	$ 6,917	$ (4,763)	$ 3,809	$ (368)	$ 5,602	$ 2
Net income	1,035	0	0	0	0	1,034	0	1,034	1
Other comprehensive income	(204)	$ 0	$ 0	0	0	0	(204)	(204)	0
Repurchases of preferred stock, shares		(4)	0
Repurchases of stock	(951)	$ 0	$ 0	0	(698)	(253)	0	(951)	0
Equity-based compensation	39	0	0	39	0	0	0	39	0
Excess tax benefits from equity-based compensation	12	0	0	12	0	0	0	12	0
Tax Settlements Associated With Equity-Based Plans	(27)	$ 0	$ 0	(27)	0	0	0	(27)	0
Tax Settlements Associated With Equity-Based Plans, Shares			0
Issuance of common stock in connection with equity-based plans (in shares)		0	3
Issuance of common stock in connection with equity-based plans	21	$ 0	$ 0	21	0	0	0	21	0
Other adjustments for equity-based plans	(2)	0	0	(2)	0	0	0	(2)	0
Redeemable noncontrolling interest adjustments to redemption value	(73)	0	0	0	0	(73)	0	(73)	0
Purchase of redeemable noncontrolling interest	0	0	0	61	0	0	(61)	0	0
Other adjustments to stockholders' equity	(3)	$ 0	$ 0	0	0	0	0	0	(3)
Ending Balance (in shares) at Dec. 31, 2015		109
Ending Balance (in shares) at Dec. 31, 2015			536
Ending Balance at Dec. 31, 2015	5,451	$ 2	$ 5	7,021	(5,461)	4,517	(633)	5,451	0
Net income	1,195	0	0	0	0	1,194	0	1,194	1
Other comprehensive income	(129)	$ 0	$ 0	0	0	0	(129)	(129)	0
Repurchases of preferred stock, shares		(9)	0
Repurchases of stock	(1,374)	$ 0	$ 0	0	(895)	(479)	0	(1,374)	0
Common Stock Dividends, Shares		0	0
Prepayment for common stock repurchase contract	(57)	$ 0	$ 0	(57)	0	0	0	(57)	0
Equity-based compensation	35	0	0	35	0	0	0	35	0
Excess tax benefits from equity-based compensation	7	0	0	7	0	0	0	7	0
Tax Settlements Associated With Equity-Based Plans	(11)	$ 0	$ 0	(11)	0	0	0	(11)	0
Tax Settlements Associated With Equity-Based Plans, Shares			0
Issuance of common stock in connection with equity-based plans (in shares)		0	5
Issuance of common stock in connection with equity-based plans	51	$ 0	$ 0	51	0	0	0	51	0
Purchase of redeemable noncontrolling interest	$ (1)	0	$ 0	0	0	0	0	0	(1)
Share conversion (in shares)	1		(2)
Share conversion	$ 0	$ 0	$ 0	0	0	0	0	0	0
Ending Balance (in shares) at Dec. 31, 2016		99
Ending Balance (in shares) at Dec. 31, 2016			543
Ending Balance at Dec. 31, 2016	5,167	$ 2	$ 5	7,046	(6,356)	5,232	(762)	5,167	0
Net income	(337)	0	0	0	0	(337)	0	(337)	0
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	0		0	4	0	(4)	0	0	0
Other comprehensive income	177	$ 0	0	0	0	0	177	177	0
Preferred Stock Modification, shares		(82)
AdjustmenttoParValuePreferredStock										$ (2)
Preferred stock modification	35			37	0	0	0	35	0		$ 0
Repurchases of preferred stock, shares		(3)
Repurchases of stock	(603)	$ 0	0	0	(381)	(222)	0	(603)	0
Prepayment for common stock repurchase contract	58	0	0	58	0	0	0	58	0
Equity-based compensation	44	0	0	44	0	0	0	44	0
Tax Settlements Associated With Equity-Based Plans	(30)	$ 0	$ 0	(30)	0	0	0	(30)	0
Tax Settlements Associated With Equity-Based Plans, Shares			(1)
Issuance of common stock in connection with equity-based plans (in shares)		0	5
Issuance of common stock in connection with equity-based plans	80	$ 0	$ 0	79	0	1	0	80	0
Redeemable noncontrolling interest adjustments to redemption value	(38)	0	0	0	0	(38)	0	(38)	0
Other adjustments to stockholders' equity	57	$ 0	$ 0	57	0	0	0	57	0
Ending Balance (in shares) at Dec. 31, 2017		14
Ending Balance (in shares) at Dec. 31, 2017			547
Ending Balance at Dec. 31, 2017	$ 4,610	$ 0	$ 5	$ 7,295	$ (6,737)	$ 4,632	$ (585)	$ 4,610	$ 0

Description Of Business And Bas

Description Of Business And Basis Of Presentation	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description Of Business And Basis Of Presentation	DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION Description of Business We are a global media company that provides content across multiple distribution platforms, including linear platforms such as pay-television ("pay-TV"), free-to-air ("FTA") and broadcast television, various digital distribution platforms and content licensing agreements. We also operate a portfolio of websites, digital direct-to-consumer products, production studios and curriculum-based education products and services. The Company presents the following business units: U.S. Networks, consisting principally of domestic television networks and digital content services, and International Networks, consisting principally of international television networks and digital content services; and Education and Other, consisting principally of curriculum-based product and service offerings and production studios. Financial information for Discovery’s reportable segments is discussed in Note 21. Basis of Presentation The consolidated financial statements include the accounts of Discovery and its majority-owned subsidiaries in which a controlling interest is maintained. For each non-wholly owned subsidiary, the Company evaluates its ownership and other interests to determine whether it should consolidate the entity or account for its ownership interest as an investment. As part of its evaluation, the Company makes judgments in determining whether the entity is a variable interest entity ("VIE") and, if so, whether it is the primary beneficiary of the VIE and is thus required to consolidate the entity. (See Note 4.) Inter-company accounts and transactions between consolidated entities have been eliminated in consolidation.

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Reclassifications The Company adopted new accounting guidance for share-based payments, deferred income taxes and statements of cash flows as of January 1, 2017. The adoption of the new guidance for deferred income taxes resulted in reclassifications of current deferred tax assets to noncurrent deferred tax assets and liabilities in the Company's balance sheet as of December 31, 2016 to conform to the current period presentation. The impact of these reclassifications is shown within the balance sheet classification of the deferred income taxes section below. The new accounting pronouncements adopted for share-based payments resulted in the reclassification of net tax windfall from financing activities to operating activities in the consolidated statement of cash flows. The impact of these reclassifications is shown within the share-based payments section below. The new accounting pronouncements adopted for cash flow statements resulted in a reclassification of debt extinguishment costs from operating activities to financing activities in the consolidated statement of cash flows. The impact of this reclassification is shown within the statement of cash flows section below. Preferred Stock Exchange As a result of the July 30, 2017, Preferred Share Exchange Agreement (the "Exchange Agreement") with Advance/Newhouse Programming Partnership ("Advance/Newhouse"), in which Discovery agreed to issue newly designated shares of Series A-1 and Series C-1 preferred stock in exchange for all outstanding shares of Discovery's Series A and Series C convertible participating preferred stock (see Note 12), historical basic and diluted earnings per share available to Series C-1 preferred stockholders, previously Series C preferred stockholders, has changed. The transactions contemplated by the Exchange Agreement were completed on August 7, 2017. Prior to the Exchange Agreement, Series C convertible preferred stock was convertible into Series C common stock at a conversion rate of 2.0 shares of Series C common stock for each share of Series C preferred stock. Following the exchange, the Series C-1 preferred stock may be converted into Series C common stock at the initial conversion rate of 19.3648 shares of Series C common stock for each share of Series C-1 preferred stock. As such, the Company has retrospectively recast basic and diluted earnings per share information for Series C preferred stock for the years ended December 31, 2016 and 2015 in order to conform with per share earnings that would have been available for Series C-1 preferred stock. (See Note 17). The Exchange Agreement did not impact historical basic and diluted earnings per share attributable to the Company's Series A, B and C common stockholders. The table below sets forth the impact of the preferred stock modification to the Company's calculated basic earnings per share. Year Ended December 31, 2016 2015 Pre-Exchange: Basic net income per share available to: Series A, B and C common stockholders $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ 3.94 $ 3.18 Post-Exchange: Basic net income per share available to: Series A, B and C common stockholders $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ 38.07 $ 30.74 Accounting and Reporting Pronouncements Adopted Statement of Cash Flows In November 2016, the Financial Accounting Standard Board ("FASB") issued guidance that reduces diversity in practice in how certain cash receipts and cash payments are classified in the statement of cash flows. The topics relevant to the Company include: (1) debt prepayment or debt extinguishment costs, which prior to adoption were classified as operating activities, but are now classified as financing activities, (2) settlement and receipt of discounts and premiums associated with our senior notes, which prior to adoption were classified as operating activities, but are now classified as financing activities when the stated interest rate is deemed not insignificant to the effective interest rate of the borrowing, (3) contingent consideration payments not made soon after a business combination date, which must be classified as financing activities up to the contingent consideration liability amount with any excess payment classified as operating activities, and (4) the election to assess distributions received from equity method investees based on the nature of distribution approach, which results in the classification of such distributions based on the nature of the activity that generated the distribution as either a return on investment (classified as cash inflows from operating activities) or a return of investment (classified as cash inflows from investing activities). The Company early adopted this guidance retrospectively effective January 1, 2017 resulting in a reclassification of $5 million of debt extinguishment costs from operating activities to financing activities in the consolidated statement of cash flows for the year ended December 31, 2015 . There was no impact on other prior periods presented for the first and second items listed above and no change in the Company's historical accounting policy was required for the third and fourth items. Share-Based Payments In March 2016 , the FASB issued guidance that simplifies how share-based payments are accounted for and presented in the financial statements. Implementation of the new accounting guidance was effective January 1, 2017 , and impacted the financial statements as follows: • Actual forfeitures will be used in the calculations of share-based compensation expense instead of estimated forfeitures. Retained earnings were decreased by approximately $4 million to affect the modified retrospective method impact of the adoption as of January 1, 2017 . • Net windfall tax benefits or deficiencies are recorded in income tax expense in the period in which they occur, whereas they were previously recorded in additional paid-in capital (“APIC”). This change has been applied prospectively. There were $7 million and $ 12 million in net tax windfall adjustments for the years ended December 31, 2016 and December 31, 2015 , respectively. • Expected cash flows from windfall tax benefits are no longer factored into the calculation of the number of shares for diluted earnings per share. This change has been applied prospectively. Net windfall tax benefits did not impact the presentation of diluted earnings per share for the years ended December 31, 2016 and December 31, 2015 by more than $0.01 per share. • Cash flows from net windfall tax benefits are classified as operating activities in the statement of cash flows presentation. Previously net windfall tax benefits were classified as financing activities. This change was applied on a retrospective basis resulting in adjustments to prior period amounts. As a result, there were $7 million and $12 million in net tax windfall adjustments for the years ended December 31, 2016 and December 31, 2015 , respectively, reclassified from financing activities to operating activities. • The Company evaluated the accounting for awards that are liability-classified and marked-to-market each accounting period and concluded that there is no change to the accounting for those awards. Balance Sheet Classification of Deferred Income Taxes In November 2015, the FASB issued guidance that removes the requirement to separate deferred tax assets and liabilities into current and noncurrent amounts, and instead requires all such amounts be classified as noncurrent on the Company's consolidated balance sheets. As a result, each tax jurisdiction will now have only one net noncurrent deferred tax asset or liability. The new guidance does not change the existing requirement that prohibits offsetting deferred tax liabilities from one jurisdiction against deferred tax assets of another jurisdiction. The Company retrospectively adopted the new guidance effective January 1, 2017. The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 ) Business Combinations In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which were recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The Company adopted this guidance effective January 1, 2016 and has applied it on a prospective basis. Accounting for Fees Paid in a Cloud Computing Arrangement In April 2015, the FASB issued explicit guidance on the recognition of fees paid by a customer for cloud computing arrangements as either the acquisition of a software license or a service contract. The Company adopted this guidance effective October 1, 2015, and there was no effect on the consolidated financial statements. Business Consolidation In February 2015, the FASB issued guidance that amends the analysis that a reporting entity performs to determine whether it should consolidate certain legal entities. The changes in this guidance include how related parties and de facto agents are considered in the primary beneficiary determination and the analysis for determining whether a fee paid to a decision maker or service provider is a variable interest. The Company adopted this guidance effective January 1, 2016, and there was no effect on the consolidated financial statements. Presentation of Financial Statements - Going Concern In August 2014, the FASB issued guidance requiring the Company to perform interim and annual assessments regarding conditions or events that raise substantial doubt about the Company's ability to continue as a going concern for a period of one year after the financial statements are issued, and to provide related disclosures, if applicable. If such conditions or events exist, an entity should disclose that there is substantial doubt about the entity's ability to continue as a going concern for a period of one year after the financial statements are issued , along with the principal conditions or events that raise substantial doubt, management's evaluation of the significance of those conditions or events in relation to the entity's ability to meet its obligations, and management's plans that are intended to mitigate those conditions or events. The Company adopted this guidance for the year ended December 31, 2016 , and concluded that as of December 31, 2017 there were no conditions or events that raise substantial doubt about the Company's ability to continue as a going concern for one year after the financial statements are issued. Accounting and Reporting Pronouncements Not Yet Adopted Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income In February 2018, the FASB issued updated guidance which permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of the tax reform legislation ("the 2017 Tax Act" or "the Tax Act") to retained earnings for each period in which the effect of the change is recorded. The update also requires entities to disclose their accounting policy for releasing income tax effects from accumulated other comprehensive income. The updated guidance is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements. Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued significant amendments to hedge accounting which expand the eligibility for hedge accounting to more financial and nonfinancial hedging strategies. The guidance is intended to align hedge accounting with companies’ risk management strategies, simplify the application of hedge accounting, and increase transparency as to the scope and results of hedging programs. In addition, the guidance amends the presentation and disclosure requirements and changes how companies assess effectiveness. The updated guidance is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements. Goodwill Under the current accounting guidance, the quantitative goodwill impairment test is performed using a two-step process. The first step of the process is to compare the fair value of a reporting unit with its carrying amount, including goodwill. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not impaired and the second step of the quantitative impairment test is not necessary. If the carrying amount of a reporting unit exceeds its fair value, the second step of the quantitative goodwill impairment test is required to be performed to measure the amount of impairment loss, if any. The second step of the quantitative goodwill impairment test compares the implied fair value of the reporting unit’s goodwill with the carrying amount of that goodwill. The implied fair value of goodwill is determined in the same manner as the amount of goodwill recognized in a business combination. In other words, the estimated fair value of the reporting unit’s identifiable net assets excluding goodwill is compared to the fair value of the reporting unit as if the reporting unit had been acquired in a business combination and the fair value of the reporting unit was the purchase price paid. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss, such as the $1.3 billion recorded for the year ended December 31, 2017 in the consolidated statements of operations, is recognized in an amount equal to that excess (see Note 8). In January 2017, the FASB issued guidance that simplifies the subsequent measurement of goodwill. The new guidance eliminates Step 2 from the goodwill impairment test, and eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment. Therefore, an entity will recognize impairment charges for the amount by which the carrying amount exceeds the reporting unit's fair value, and the same impairment assessment applies to all reporting units. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017 . The amendments in this update must be adopted on a prospective basis for the annual or any interim goodwill impairment tests beginning after December 15, 2019 . If the Company had early adopted this accounting pronouncement, the impact of the current period goodwill impairment would have been approximately $100 million , substantially less than the impairment charge recorded under the current guidance. Accounting changes and error corrections In January 2017, the FASB issued guidance which states that registrants should consider additional qualitative disclosures if the impact of an issued but not yet adopted ASU is unknown or cannot be reasonably estimated and to include a description of the effect of the accounting policies that the registrant expects to apply, if determined. This guidance is effective immediately. Transition guidance in certain issued but not yet adopted standards has been updated to reflect this amendment. Clarifying the definition of a business In January 2017, the FASB issued guidance that amends the definition of a business and provides a threshold which must be considered to determine whether a transaction is an acquisition (or disposal) of an asset or a business. Under the current accounting guidance, the minimum inputs and processes required for a “set” of assets and activities to meet the definition of a business is not specified. That lack of clarity has led to broad interpretations of the definition of a business. Under this guidance, when substantially all of the fair value of gross assets acquired is concentrated in a single asset (or group of similar assets), the assets acquired would not represent a business. In addition, in order to be considered a business, an acquisition would have to include at a minimum an input and a substantive process that together significantly contribute to the ability to create an output. The amended guidance also narrows the definition of outputs by more closely aligning it with how outputs are described in FASB guidance for revenue recognition. The guidance is effective on a prospective basis beginning January 1, 2018 and is not expected to have a material impact on the Company’s consolidated financial statements. Income Taxes In October 2016, the FASB issued guidance that simplifies the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. The new guidance includes requirements to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs, and therefore eliminates the exception for an intra-entity transfer of an asset other than inventory. The new standard is effective January 1, 2018. The Company is currently analyzing the impact of the pronouncement to the consolidated financial statements. Leases In February 2016 , the FASB issued guidance on leases that will require lessees to recognize almost all of their leases on the balance sheet by recording a right-of-use asset and liability. The new standard will be effective for reporting periods beginning after December 15, 2018 , and the new accounting guidance may be applied at the beginning of the earliest comparative period presented in the year of adoption or at effective date without applying the provisions of the new guidance to comparative periods presented. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements; however, it is expected that assets and liabilities will increase materially when operating leases are recorded under the new standard. The method of transition will be determined when the Company has completed its evaluation. Recognition and Measurement of Financial Instruments In January 2016 , the FASB issued guidance regarding the classification and measurement of financial instruments, which among other changes in accounting and disclosure requirements, replaces the cost method of accounting for non-marketable equity securities with a model for recognizing impairments and observable price changes, and also eliminates the available-for-sale classification for marketable equity securities. The standard requires equity securities, including available-for-sale ("AFS") securities, to be measured at fair value with changes in the fair value recognized through net income, superseding the guidance permitting entities to record gains and losses on equity securities with readily determinable fair values in accumulated other comprehensive income. Investments accounted for under the equity method of accounting or that result in consolidation are not included within the scope of this update. The new standard will affect the Company's accounting for AFS securities for reporting periods beginning after December 15, 2017 . The Company will apply the guidance on a modified retrospective basis. The transition adjustment to reclassify accumulated other comprehensive income to retained earnings is expected to be $26 million . (See Note 12.) Revenue from Contracts with Customers In May 2014 , the FASB issued an accounting pronouncement related to revenue recognition, which applies a single, comprehensive revenue recognition model for all contracts with customers. The core principle of the new guidance is that the Company will recognize revenue from the transfer of promised goods or services to customers at an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those goods or services. Subsequent to the issuance of the May 2014 guidance, several clarifications and updates have been issued by the FASB on this topic, the most recent of which was issued in December 2016. Many of these clarifications and updates to the guidance, as well as a number of interpretive issues, apply to companies in the media and entertainment industry. The guidance requires new or expanded disclosures related to the judgments made by companies when following the framework. The Company is nearing completion of its assessment of the impact of adopting this new guidance, and the Company will implement the new revenue standard beginning January 1, 2018. The Company currently does not anticipate that the adoption of the new guidance will have a material impact on the Company's financial statements, principally because the Company does not expect significant changes in the way it will record distribution or advertising revenues. The Company will apply the guidance on a modified retrospective basis. Use of Estimates The preparation of financial statements in accordance with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates, judgments and assumptions that affect the amounts and disclosures reported in the consolidated financial statements and accompanying notes. Management continually re-evaluates its estimates, judgments and assumptions, and management’s evaluations could change. These estimates are sometimes complex, sensitive to changes in assumptions and require fair value determinations using Level 3 fair value measurements. Actual results may differ materially from those estimates. Estimates and judgments inherent in the preparation of the consolidated financial statements include accounting for asset impairments, revenue recognition, allowances for doubtful accounts, content rights, depreciation and amortization, business combinations, share-based compensation, income taxes, other financial instruments, contingencies, and the determination of whether the Company is the primary beneficiary of entities in which it holds variable interests. Consolidation The Company has ownership and other interests in various entities, including corporations, partnerships, and limited liability companies. For each such entity, the Company evaluates its ownership and other interests to determine whether it should consolidate the entity or account for its ownership interest as an investment. As part of its evaluation, the Company initially determines whether the entity is a VIE and, if so, whether it is the primary beneficiary of the VIE. An entity is generally a VIE if it meets any of the following criteria: (i) the entity has insufficient equity to finance its activities without additional subordinated financial support from other parties, (ii) the equity investors cannot make significant decisions about the entity’s operations, or (iii) the voting rights of some investors are not proportional to their obligations to absorb the expected losses of the entity or receive the expected returns of the entity and substantially all of the entity’s activities involve or are conducted on behalf of the investor with disproportionately few voting rights. The Company consolidates VIEs for which it is the primary beneficiary, regardless of its ownership or voting interests. The primary beneficiary is the party involved with the VIE that (i) has the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance, and (ii) has the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. Upon inception of a variable interest or the occurrence of a reconsideration event, the Company makes judgments in determining whether entities in which it invests are VIEs. If so, the Company makes judgments to determine whether it is the primary beneficiary and is thus required to consolidate the entity. If it is concluded that an entity is not a VIE, then the Company considers its proportional voting interests in the entity. The Company consolidates majority-owned subsidiaries in which a controlling financial interest is maintained. A controlling financial interest is determined by majority ownership and the absence of substantive third-party participating rights. Ownership interests in entities for which the Company has significant influence that are not consolidated under the Company’s consolidation policy are accounted for as equity method investments. Related party transactions between the Company and its equity method investees have not been eliminated. (See Note 19.) Investments The Company holds investments in equity method investees, cost method investees and available-for-sale securities. Investments in equity method investees are those for which the Company has the ability to exercise significant influence, but does not control and is not the primary beneficiary. Significant influence typically exists if the Company has a 20% to 50% ownership interest in the venture unless persuasive evidence to the contrary exists. Under this method of accounting, the Company typically records its proportionate share of the net earnings or losses of equity method investees and a corresponding increase or decrease to the investment balances. Cash payments to equity method investees such as additional investments, loans and advances and expenses incurred on behalf of investees, as well as payments from equity method investees such as dividends, distributions and repayments of loans and advances are recorded as adjustments to investment balances. For the Company's equity method investments in renewable energy limited liability companies where the capital structure of the equity investment results in different liquidation rights and priorities than what is reflected by the underlying percentage ownership interests, the Company's proportionate share of net earnings is accounted for using the Hypothetical Liquidation at Book Value ("HLBV") methodology available under the equity method of accounting. When applying HLBV, the Company determines the amount that would be received if the investment were to liquidate all of its assets and distribute the resulting cash to the investors based on contractually defined liquidation priorities, assuming the entity continues as a going concern. The change in the Company's claim on the investee's book value in accordance with GAAP at the beginning and the end of the reporting period, after adjusting for any contributions or distributions, is the Company's share of the earnings or losses for the period. The Company evaluates its equity method investments for impairment whenever events or changes in circumstances indicate that the carrying amounts of such investments may not be recoverable. (See "Asset Impairment Analysis" below.) Cost method investments include ownership rights that either (i) do not meet the definition of in-substance common stock or (ii) do not provide the Company with control or significant influence and these investments do not have readily determinable fair values. Cost method investments are recorded at the lower of cost or fair value. Investments in entities or other securities in which the Company has no control or significant influence and is not the primary beneficiary and have a readily determinable fair value are accounted for at fair value based on quoted market prices are classified as either trading securities or available-for-sale securities. For investments classified as trading securities, which include securities held in a separate trust in connection with the Company’s deferred compensation plan, unrealized and realized gains and losses related to the investment and corresponding liability are recorded in earnings as a component of other income (expense), net , on the consolidated statements of operations. For investments classified as AFS, which include investments in common stock, unrealized gains and losses are recorded, net of income taxes, in other comprehensive (loss) income until the security is sold or considered impaired. If declines in the value of AFS securities are determined to be other-than-temporary, a loss is recorded in earnings in the current period as a component of other income (expense), net on the consolidated statements of operations. (See "Asset Impairment Analysis" below.) For purposes of computing realized gains and losses, the Company determines cost on a specific identification basis. Cash obtained as a result of the Company's debt issuance in September 2017 is invested into short-term instruments that qualify as cash and cash equivalents. Any accrued interest received after maturity is reinvested into additional short-term instruments. These investments are anticipated to be used to partially fund the Scripps Networks Interactive, Inc. ("Scripps Networks") acquisition. In the interim, the Company has full access to these proceeds. Foreign Currency The reporting currency of the Company is the U.S. dollar. The functional currency of most of the Company’s international subsidiaries is the local currency. Assets and liabilities, including inter-company balances for which settlement is anticipated in the foreseeable future, denominated in foreign currencies are translated at exchange rates in effect at the balance sheet date. Foreign currency equity balances are translated at historical rates. Revenues and expenses denominated in foreign currencies are translated at average exchange rates for the respective periods. Foreign currency translation adjustments are recorded in accumulated other comprehensive income. Transactions denominated in currencies other than subsidiaries’ functional currencies are recorded based on exchange rates at the time such transactions arise. Changes in exchange rates with respect to amounts recorded in the consolidated balance sheets related to these items will result in unrealized foreign currency transaction gains and losses based upon period-end exchange rates. The Company also records realized foreign currency transaction gains and losses upon settlement of the transactions. Foreign currency transaction gains and losses are included in other (expense) income, net , and totaled a loss of $83 million , a gain of $75 million , and a loss of $103 million for 2017 , 2016 and 2015 , respectively. Cash flows from the Company's operations in foreign countries are generally translated at the weighted average rate for the applicable period in the consolidated statements of cash flows. The impacts of material transactions are recorded at the applicable spot rates as of the transaction date in the consolidated statements of operations and cash flows. The effects of exchange rates on cash balances held in foreign currencies are separately reported in the Company's consolidated statements of cash flows. Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid investments with original maturities of 90 days or less. Receivables Receivables include amounts billed and currently due from customers and are presented net of an estimate for uncollectible accounts. The Company evaluates outstanding receivables to assess collectability. In performing this evaluation, the Company analyzes market trends, economic conditions, the aging of receivables and customer specific risks. Using this information, the Company reserves an amount that it estimates may not be collected. The Company does not require collateral with respect to trade receivables. Content Rights Content rights principally consist of television series, specials, films and sporting events. Content aired on the Company’s television networks is sourced from a wide range of third-party prod

Acquisitions And Dispositions

Acquisitions And Dispositions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions And Dispositions	ACQUISITIONS AND DISPOSITIONS Acquisitions Scripps Networks Interactive, Inc. On February 26, 2018 , the U.S. Department of Justice notified the Company that it has closed its investigation into Discovery's agreement for a plan of merger to acquire Scripps Networks in a cash-and-stock transaction. The estimated merger consideration for the acquisition totals $12.0 billion , including cash of $8.4 billion and stock of $3.6 billion based on the Series C common stock price as of January 31, 2018 . In addition, the Company will assume Scripps Networks' net debt of approximately $2.7 billion . The transaction is expected to close in early 2018. Scripps Networks shareholders will receive $63.00 per share in cash and a number of shares of Discovery's Series C common stock that is determined in accordance with a formula and subject to a collar based on the volume weighted average price of the Company's Series C common stock. The formula is based on the volume weighted average price of Discovery's Series C common stock over the 15 trading days ending on the third trading day prior to closing (the “Average Discovery Price”). Scripps Networks shareholders will receive 1.2096 shares of Discovery's Series C common stock if the Average Discovery Price is below $22.32 , and 0.9408 shares of Discovery's Series C common stock if the Average Discovery Price is above $28.70 . The intent of the range was to provide Scripps Networks shareholders with $27.00 of value per share in Discovery Series C common stock; if the Average Discovery Price is greater than or equal to $22.32 but less than or equal to $28.70 , Scripps Networks shareholders will receive a proportional number of shares between 1.2096 and 0.9408 . If the Average Discovery Price is below $25.51 , Discovery has the option to pay additional cash instead of issuing more shares above the 1.0584 conversation ratio required at $25.51 . The cash payment is equal to the product of the additional shares required under the collar formula multiplied by the Average Discovery Price; for example, if the Average Discovery Price were $22.32 with a conversion ratio of 1.2096 , the Company could offer shares at the 1.0584 ratio and pay for the difference associated with the incremental shares in cash. Outstanding employee equity awards or share-based awards that vest upon the change of control will be acquired with a similar combination of cash and shares of Discovery Series C common stock pursuant to terms specified in the Merger Agreement. Therefore, the merger consideration will fluctuate based upon changes in the share price of Discovery Series C common stock and the number of Scripps Networks common shares, stock options, and other equity-based awards outstanding on the closing date. Discovery will also pay certain transaction costs incurred by Scripps Networks. The post-closing impact of the formula was intended to result in Scripps Networks’ shareholders owning approximately 20% of Discovery’s fully diluted common shares and Discovery’s shareholders owning approximately 80% . The Company will utilize debt (see Note 9) and cash on hand to finance the cash portion of the transaction. The transaction is subject to regulatory approvals and other customary closing conditions. John C. Malone, Advance/Newhouse and members of the Scripps family entered into voting agreements to vote in favor of the transactions and the stockholders of both Discovery and Scripps Networks approved the transaction on November 17, 2017 . In addition, Advance/Newhouse has provided its consent, in its capacity as the holder of Discovery’s outstanding shares of Series A preferred stock, for Discovery to enter into the Merger Agreement and consummate the merger. In connection with this consent, Discovery and Advance/Newhouse entered into an exchange agreement pursuant to which Advance/Newhouse exchanged all of its shares of Series A and Series C preferred stock of Discovery for shares of newly designated Series A-1 and Series C-1 preferred stock of Discovery. The exchange transaction did not change the aggregate number of shares of Discovery’s Series A common stock and Series C common stock that are beneficially owned by Advance/Newhouse or change voting rights or liquidation preferences afforded to Advance/Newhouse. The $35 million impact of the modification has been recorded as a component of selling, general and administrative expense. (See Note 12 and Note 17.) All of Discovery's direct costs of the Scripps Networks acquisition will be reflected as a component of selling, general and administrative expense in the consolidated statements of operations. The following table summarizes the components of the estimated merger consideration (in millions of dollars and shares, except for per share amounts, share conversion ratio, stock option conversion ratio, average cash consideration and average equity consideration). The estimated merger consideration is based on the number of Scripps Networks shares outstanding as of December 31, 2017 , and utilizes a January 31, 2018 transaction closing date to compute the equity portion of the purchase price. Outstanding Scripps Networks equity Scripps Networks shares outstanding 130 Cash consideration per share $ 63.00 Estimated cash portion of purchase price $ 8,193 Scripps Networks shares outstanding 130 Share conversion ratio 1.1316 Discovery Series C common stock assumed to be issued 147 Discovery Series C common stock price per share $ 23.86 Estimated equity portion of purchase price $ 3,511 Outstanding shares under Scripps Networks share-based compensation programs Shares under Scripps Networks share-based compensation programs 3 Scripps Networks share-based compensation converting to cash (70%) 2 Average cash consideration (per share less applicable exercise price) $ 50.34 Estimated cash portion of purchase price $ 114 Scripps Networks share-based compensation converting to Discovery Series C common stock (30%) 1 Stock option conversion ratio (based on intrinsic value per award) 3 Discovery Series C common stock (1) or options (2) assumed to be issued 3 Average equity consideration (intrinsic value of Discovery Series C common stock or options to be issued as consideration) $ 12.84 Estimated equity portion of purchase price for share awards $ 45 Scripps Networks transaction costs required to be paid by Discovery $ 105 Total estimated consideration to be paid $ 11,968 Balances reflect rounding of dollar and share amounts to millions, which may result in differences for recalculated amounts compared with the amounts presented above. Merger Consideration Sensitivity The table below illustrates the potential impact to the total estimated outstanding Discovery Series C common stock to be issued assuming that the stock portion of the consideration for outstanding Scripps shares were converted to shares of Discovery Series C common stock at either the low-end or the high-end of the collar range. For the purposes of this calculation, the total number of Scripps outstanding shares has been assumed to be the same as in the table above. The stock prices used to determine the equity portion of the consideration in each scenario is based on Discovery Series C common stock price at the low-end and the high-end of the collar (in millions of dollars and shares, except for conversion ratio). Discovery Series C Common Stock (DISCK) Shares to Issue and Total Estimated Consideration to be Paid Minimum Maximum Scripps shares outstanding as of December 31, 2017 130 130 Average Discovery price - Series C common stock $ 22.32 $ 28.70 Conversion ratio 1.2096 0.9408 Discovery Series C common stock to be issued for estimated Scripps shares outstanding 157 122 Total estimated consideration to be paid $ 11,968 $ 11,968 If the average price of Discovery Series C common stock is above the collar maximum or below the collar minimum, the total estimated consideration to be paid will increase or decrease accordingly from the amount shown in the table above. The merger will be accounted for as a business combination using the acquisition method of accounting, which will establish a new basis of accounting for all identifiable assets acquired and liabilities assumed at fair value as of the date control is obtained. Accordingly, the costs to acquire such interests will be allocated to the underlying net assets based on their respective fair values, including noncontrolling interests. Any excess of the purchase price over the estimated fair value of the net assets acquired will be recorded as goodwill. OWN On November 30, 2017 , the Company acquired from Harpo, Inc. ("Harpo") a controlling interest in OWN, increasing Discovery’s ownership stake from 49.50% to 73.99% . OWN is a pay-TV network and website that provides adult lifestyle and entertainment content, which is focused on African Americans. Discovery paid $70 million in cash and recognized a gain of $33 million to account for the difference between the carrying value and the fair value of the previously held 49.50% equity interest. The price included an assessment of fair value of the equity interest in the network, subject to the impact of the note payable to Discovery. The gain is included in other (expense) income, net in the Company's consolidated statements of operations (see Note 18). Discovery consolidated OWN under the VIE consolidation model upon closing of the transaction. As a result, the accounting for OWN was changed from an equity method investment to a consolidated subsidiary. The Company applied the acquisition method of accounting to OWN’s business, whereby the excess of the fair value of the business over the fair value of identifiable net assets was allocated to goodwill. The goodwill reflects the workforce and synergies expected from broader exposure to the self-discovery and self-improvement entertainment sector. The goodwill recorded as part of this acquisition is included in the U.S. Network reportable segment and is not amortizable for tax purposes. Intangible assets consist of advertiser backlog, advertiser relationships and affiliate relationships with a weighted average estimated useful life of 9 years. The preliminary opening balance sheet is subject to adjustment based on final assessment of the fair values of certain acquired assets, principally intangibles, and certain contingent liabilities. The Company used discounted cash flow ("DCF") analyses, which represent Level 3 fair value measurements, to assess certain components of its purchase price allocation. As the Company finalizes the fair value of assets acquired and liabilities assumed, additional purchase price adjustments may be recorded during the measurement period. The Company will reflect measurement period adjustments, if any, in the period in which the adjustments occur. The preliminary fair value of assets acquired and liabilities assumed, as well as a reconciliation to cash consideration transferred is presented in the table below (in millions). November 30, 2017 Intangible assets $ 295 Content rights 176 Accounts receivable 84 Other assets 26 Other liabilities (230) Net assets acquired $ 351 Goodwill 136 Remeasurement gain on previously held equity interest (33) Carrying value of previously held equity interest (329) Redeemable noncontrolling interest (55) Cash consideration transferred $ 70 Following the acquisition of the incremental equity interest and change to governance provisions, the Company has determined that it is now the primary beneficiary of OWN as Discovery obtained control of the Board of Directors and operational rights that significantly impact the economic performance of the business such as programming and marketing, and selection of key personnel. As the primary beneficiary, Discovery includes OWN's assets, liabilities and results of operations in the Company's consolidated financial statements. As of December 31, 2017 , the carrying amounts of assets and liabilities of the consolidated VIE were $707 million and $505 million , respectively. The fair value of the noncontrolling interest retained by Harpo was computed based on Harpo's contractual claims to the underlying net assets of the business, which are partially subordinate to the Company's given the Company's historical funding of OWN's losses. The loans funded by Discovery to launch the network require repayment prior to equity distributions to partners. Harpo has the right to require the Company to purchase its remaining non-controlling interest during 90-day windows beginning on July 1, 2018 and every two and half years thereafter through January 1, 2026. As OWN’s put right is outside the Company's control, OWN’s noncontrolling interest is presented as redeemable noncontrolling interest outside of permanent equity on the Company's consolidated balance sheet. (See Note 11.) The Enthusiast Network, Inc. On September 25, 2017 , the Company contributed its linear cable network focused on cars and motor sports, Velocity, to a new joint venture ("VTEN"), with GoldenTree Asset Management L.P. ("GoldenTree"). GoldenTree's contributions to the joint venture included businesses from The Enthusiast Network, Inc. ("TEN"), primarily MotorTrend.com, Motor Trend YouTube channel and the Motor Trend OnDemand OTT service. TEN did not contribute its print businesses to the joint venture. The joint venture will establish a portfolio of digital content, social groups, live events and original content focused on the automotive audience. In exchange for their contributions, Discovery and GoldenTree received 67.5% and 32.5% ownership of the new joint venture, respectively. Discovery consolidated the joint venture under the voting interest consolidation model upon the closing of the transaction. As the Company controlled Velocity and continues to control Velocity after the transaction, the change in the value of the Company's ownership interest was accounted for as an equity transaction and no gain or loss was recognized in the Company's consolidated statements of operations. The Company applied the acquisition method of accounting to TEN's contributed businesses, whereby the excess of the fair value of the contributed business over the fair value of identifiable net assets was allocated to goodwill. The goodwill reflects the workforce and synergies expected from broader exposure to the automotive entertainment sector. The goodwill recorded as part of this acquisition is included in the U.S. Network reportable segment and is not amortizable for tax purposes. Intangible assets primarily consist of trade names, licensing agreements and customer relationships with a weighted average estimated useful life of 16 years . The Company used DCF analyses, which represent Level 3 fair value measurements, to assess certain components of its purchase price allocation. The fair value of net assets acquired includes measurement period adjustments primarily due to finalization of the valuation of intangible assets recorded against goodwill. The fair value of the assets acquired and liabilities assumed is presented in the table below (in millions). Preliminary September 25, 2017 Measurement Period Adjustments Final September 25, 2017 Goodwill $ 59 $ 16 $ 75 Intangible assets 71 (18 ) 53 Property plant and equipment, net 16 1 17 Other assets acquired 6 — 6 Liabilities assumed (8 ) 1 (7) Net assets acquired $ 144 $ — $ 144 Discovery has a fair value call right exercisable during 30 day windows beginning September 2022 and March 2024 to require GoldenTree to sell its entire ownership interest in the joint venture at fair value. GoldenTree has a fair value put right exercisable during 30 day windows beginning in March 2021, September 2022 and March 2024 that requires Discovery to either purchase all of GoldenTree's interest in the joint venture at fair value or participate in an initial public offering for the joint venture. GoldenTree's 32.5% noncontrolling interest in the joint venture is presented as redeemable noncontrolling interest outside of permanent equity on the Company's consolidated balance sheet. The opening balance sheet value recognized for the redeemable noncontrolling interest upon closing was $82 million , based on GoldenTree's ownership interest in the book value of Velocity and fair value of GoldenTree's contribution. The balance was subsequently increased by $38 million to adjust the redemption value to fair value of $120 million . (See Note 11.) Eurosport International and France On March 31, 2015 the Company acquired an additional 31% interest in Eurosport France for €36 million ( $38 million ). This transaction gave the Company a 51% controlling stake in Eurosport. The Company recognized gains of $2 million for the year ended December 31, 2015 to account for the difference between the carrying value and the fair value of the previously held 20% equity method investments in Eurosport France and Eurosport International. The gains were included in other (expense) income, net in the Company's consolidated statements of operations. (See Note 18.) On October 1, 2015, TF1 put its remaining 49% interest in Eurosport to the Company for €491 million ( $548 million ). (See Note 11.) Eurosport is a leading pan-European sports media platform. The flagship Eurosport network focuses on regionally popular sports, such as tennis, skiing, cycling and motor sports. Eurosport’s brands and platforms also include Eurosport HD (high definition simulcast), Eurosport 2, Eurosport 2 HD and Eurosportnews. The acquisitions are intended to enhance the Company's pay-TV offerings in Europe and increase the growth of Eurosport. The Company used a DCF analysis, which represent Level 3 fair value measurements, to assess certain components of the Eurosport purchase price allocations. The fair value of the assets acquired, liabilities assumed, noncontrolling interests recognized and the remeasurement gains recorded on the previously held equity interests is presented in the table below (in millions). Eurosport France March 31, 2015 Goodwill $ 69 Intangible assets 40 Other assets acquired 25 Cash 35 Removal of TF1 put right 2 Currency translation adjustment (6 ) Remeasurement gain on previously held equity interest (2 ) Liabilities assumed (30 ) Deferred tax liabilities (14 ) Redeemable noncontrolling interest (Note 11) (60 ) Carrying value of previously held equity interest (21 ) Net assets acquired $ 38 The goodwill reflects the workforce and synergies expected from increased pan-European market penetration as the operations of Eurosport and the Company are combined. The goodwill recorded as part of this acquisition is included in the International Networks reportable segment and is not amortizable for tax purposes. Intangible assets primarily consist of distribution and advertising customer relationships, advertiser backlog and trademarks with a weighted average estimated useful life of 10 years. Other In 2017 and 2015 , the Company acquired other businesses for total cash and contingent consideration of $4 million and $91 million , net of cash acquired, respectively. Total consideration as of December 31, 2015 included contingent consideration of $13 million , of which $2 million was paid during 2016. The acquisitions included FTA networks in Poland, Italy and Turkey, cable networks in Denmark and a pay-TV sports channel in Asia. The goodwill reflects the synergies and regional market penetration from combining the operations of these acquisitions with the Company's operations. Pro Forma Financial Information The Company did not have material pro forma information to present for 2017, 2016 and 2015. The Company's 2017 business combinations are not material individually or in the aggregate, the Company had no 2016 business combinations, and the Company's 2015 business combinations are also not material individually or in the aggregate. Dispositions Education Sale On February 26, 2018 , the Company announced the planned sale of a controlling equity stake in its education business in the first half of 2018 to Francisco Partners for cash of $120 million . No loss is expected upon sale. The Company will retain an equity interest. Additionally, the Company will have ongoing license agreements which are considered to be at fair value. As of December 31, 2017, the Company determined that the education business did not meet the held for sale criteria, as defined in GAAP as management had not committed to a plan to sell the assets. Raw and Betty Studios, LLC On April 28, 2017 , the Company sold Raw and Betty to All3Media. All3Media is a U.K. based television, film and digital production and distribution company. The Company owns 50% of All3Media and accounts for its investment in All3Media under the equity method of accounting. The Company recorded a loss of $4 million for the disposition of these businesses for the year ended December 31, 2017 . The loss on disposition of Raw and Betty included $38 million in net assets, including $30 million of goodwill. Raw and Betty were components of the studios operating segment reported with Education and Other. Group Nine Transaction On December 2, 2016 , the Company recorded a pre-tax gain of $50 million upon disposition of its digital network Seeker and production studio SourceFed, following its contribution of the businesses and $100 million in cash for the formation of a new joint venture, Group Nine Media, Inc. ("Group Nine Media"), on December 2, 2016 ("Group Nine Transaction"). Group Nine Media includes Thrillist Media Group, NowThis Media and TheDodo.com. As a result of the transaction, Discovery obtained a non-controlling ownership interest in the preferred stock of Group Nine Media, which is accounted for under the cost method of accounting. As of December 31, 2017 , the Company owns a 42% minority interest in Group Nine Media with a carrying value of $212 million . (See Note 4.) The gain on contribution of the digital networks business included the disposition of $32 million in net assets, including $22 million of goodwill allocated to the transaction based on the relative fair values of the digital networks business disposed of and the portion of the U.S. Networks reporting unit that was retained. Russia On October 7, 2015 , Discovery recorded a loss of $5 million upon the deconsolidation of its Russian business following its contribution to a joint venture (the “New Russian Business”) with a Russian media company, National Media Group ("NMG"). The New Russian Business was established to comply with changes in Russian legislation that limit foreign ownership of media companies in Russia. No cash consideration was exchanged in the transaction. NMG contributed a FTA license which enables advertising for the New Russian Business. As part of the transaction, Discovery obtained a 20% ownership interest in the New Russian Business, which is accounted for under the equity method of accounting. The loss on contribution of the Russian business included $15 million of goodwill allocated to the transaction based on the relative fair values of the Russian business disposed of and the portion of the reporting unit that was retained. Although Discovery no longer consolidates the Russian business, Discovery earns revenue by providing content and brands to the New Russian Business under long-term licensing arrangements. (See Note 19.) The Russian business was included in the International Networks reportable segment; the licensing arrangements with the New Russian Business are reported as distribution revenue in the International Networks reportable segment. (See Note 21.) Radio On June 30, 2015 , Discovery sold its radio businesses in Northern Europe to Bauer Media Group ("Bauer") for total consideration, net of cash disposed of €72 million ( $80 million ), which included €54 million ( $61 million ) in cash and €18 million ( $19 million ) of contingent consideration. The cumulative gain on the disposal is $1 million . Based on the final resolution and receipt of contingent consideration payable, Discovery recorded a pre-tax gain of $13 million for the year ended December 31, 2016 . The Company had previously recorded a $12 million loss including estimated contingent consideration as disclosed for the year ended December 31, 2015 . The Company determined that the disposals noted above did not meet the definition of a discontinued operation because the dispositions do not represent strategic shifts that have a significant impact on the Company's operations and consolidated financial results.

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Investments [Abstract]
Investments	INVESTMENTS The Company’s investments consisted of the following (in millions). December 31, Category Balance Sheet Location 2017 2016 Cash equivalents: Time deposits Cash and cash equivalents $ 1,305 $ — Trading securities: Money market funds Cash and cash equivalents 2,707 — Mutual funds Prepaid expenses and other current assets 182 160 Equity method investments: Equity investments Equity method investments 335 246 OWN advances and note receivable Equity method investments — 311 AFS securities: Common stock Other noncurrent assets 82 64 Common stock - pledged Other noncurrent assets 82 64 Cost method investments Other noncurrent assets 295 245 Total investments $ 4,988 $ 1,090 Money Market Funds, Time Deposits and U.S. Treasury Securities During 2017, the Company issued $6.8 billion in senior notes to fund the anticipated Scripps Networks acquisition. (See Note 3 and Note 9.) Of these total proceeds, $2.7 billion were invested in money market funds, $1.3 billion were invested in time deposit accounts, and the remainder was invested in highly liquid, short-term instruments with original maturities of 90 days or less. These investments are classified as cash and cash equivalents on the consolidated balance sheet and are anticipated to be used for the Scripps Networks acquisition. In the interim, the Company has full access to these proceeds. Of the $6.8 billion in debt proceeds, approximately $5.9 billion is subject to a special mandatory redemption provision that requires the Company to redeem the notes for a price equal to 101% of their principal amount, plus any accrued and unpaid interest on the notes, in the event that the Scripps Networks acquisition has not closed or the agreement is terminated prior to August 30, 2018 . While the Company expects to complete the Scripps Networks acquisition by the required date, unanticipated developments could delay or prevent the acquisition. Mutual Funds Trading securities include investments in mutual funds held in a separate trust, which are owned as part of the Company’s supplemental retirement plan. (See Note 5.) Equity Method Investments The Company makes investments that support its underlying business strategy and enable it to enter new markets and develop programming. Almost all equity method investees are privately owned. With the exception of the OWN investment prior to the November 30, 2017 acquisition (see Note 3), and certain investments in renewable energy projects accounted for using the HLBV methodology, carrying values of the Company’s equity method investments are consistent with its ownership in the underlying net assets of the investees. Certain of the Company's equity method investments are VIEs, for which the Company is not the primary beneficiary. As of December 31, 2017 , the Company’s maximum estimated exposure for all its VIEs including the investment carrying values, unfunded contractual commitments, and guarantees made on behalf of VIEs was approximately $204 million . The Company's maximum estimated exposure excludes the non-contractual future funding of VIEs. The aggregate carrying values of these VIE equity method investments were $181 million and $426 million as of December 31, 2017 and 2016 , respectively. The Company recognized its portion of VIE operating results with losses of $182 million , earnings of $7 million and earnings of $30 million for 2017 , 2016 and 2015 , respectively, in income from equity investees, net on the consolidated statements of operations. Renewable Energy Investments The Company invested in limited liability companies that sponsor renewable energy projects related to solar energy during the years ended December 31, 2017 and December 31, 2016 , for the amounts of $322 million and $63 million , respectively. There were no investments in 2015 . The Company expects these investments to result in tax benefits received, which reduce the Company's tax liability, and cash flows from the operations of the investees. These investments are considered VIEs of the Company. The Company accounts for these investments under the equity method of accounting. While the Company possesses rights that allow it to exercise significant influence over the investments, the Company does not have the power to direct the activities that will most significantly impact their economic performance, such as the investee's ability to obtain sufficient customers or control solar panel assets. Once a stipulated return on investment is garnered by the Company, the investment allocations to the Company are significantly reduced. Accordingly, the Company applies the HLBV method for recognizing the Company's proportionate share of the investments' net earnings or losses. The Company recognized $251 million and $24 million of losses on these investments as of December 31, 2017 and December 31, 2016 , respectively. The losses are reflected as a component of (loss) income from equity investees, net on the Company's consolidated statements of operations. The Company has recorded income tax benefits associated with these investments of $294 million post-tax reform and $26 million for 2017 and 2016 , respectively. These benefits are comprised of $83 million post-tax reform and $9 million from the entities' passive losses and $211 million post-tax reform and $17 million from investment tax credits for 2017 and 2016, respectively. The Company accounts for investment tax credits utilizing the flow through method. As of December 31, 2017 and December 31, 2016 , the Company's carrying value of renewable energy investments were $98 million and $39 million , respectively. The Company has $20 million of future funding commitments for these investments as of December 31, 2017 , which are cancelable under limited circumstances. The Company has concluded that losses incurred on these investments to-date are not indicative of an other-than-temporary impairment due to the nature of these investments. Losses in the early stages of investments in companies that sponsor renewable energy projects are not uncommon, and the Company expects improved performance from these investments in future periods. Other Equity Method Investments At December 31, 2017 and December 31, 2016 , the Company's other equity method investments included All3Media, a Russian cable television business, Mega TV in Chile, and certain joint ventures in Canada. The Company acquired other equity method investments, largely to enhance the Company's digital distribution strategies, particularly for Eurosport Player, and made additional contributions to existing equity method investments totaling $73 million during 2017 . Significant Subsidiaries The table set forth below presents selected financial information for investments accounted for under the equity method. Because renewable energy projects discussed above are accounted for under the HLBV equity method of accounting, the Company's equity method losses do not directly correlate with the GAAP results of the investees presented below. The selected statement of operations information for each of the three years ended December 31, 2017 , 2016 , and 2015 and the selected balance sheet information as of December 31, 2017 and 2016 (in millions). 2017 2016 2015 Selected Statement of Operations Information: Revenues $ 1,780 $ 1,617 $ 1,324 Cost of sales 1,100 998 853 Operating income 76 83 42 Pre-tax income (loss) from continuing operations before extraordinary items 16 (78 ) (42 ) After-tax net loss (27 ) (98 ) (42 ) Net loss attributable to the entity (27 ) (99 ) (42 ) Selected Balance Sheet Information: Current assets $ 1,002 $ 884 Noncurrent assets 1,946 1,646 Current liabilities 701 752 Noncurrent liabilities 1,008 1,177 Redeemable preferred stock 476 — Non-controlling interests 6 8 AFS Securities On November 12, 2015 , the Company acquired 5 million shares, or 3% , of Lions Gate Entertainment Corp. ("Lionsgate"), an entertainment company, for $195 million . Lionsgate operates in the motion picture production and distribution, television programming and syndication, home entertainment, family entertainment and digital distribution businesses. As the shares have a readily determinable fair value and the Company has the intent to retain the investment, the shares are classified as AFS securities. The accumulated amounts associated with the components of the Company's AFS securities, which are included in other non-current assets, are summarized in the table below. December 31, 2017 2016 Cost $ 195 $ 195 Accumulated change in the value of: Hedged AFS recognized in other expense, net (1 ) (19 ) Unhedged AFS recorded in other comprehensive income 32 14 Other-than-temporary impairment of AFS Securities (62 ) (62 ) Carrying value $ 164 $ 128 The Company hedged 50% of the shares with an equity collar (the “Lionsgate Collar”) and pledged those shares as collateral to the derivative counter party. In the application of hedge accounting, when the share price of Lionsgate is within the boundaries of the collar and the hedge has no intrinsic value, the Company records the gains or losses on the Lionsgate AFS securities as a component of other comprehensive income (loss) . When the share price of the Lionsgate AFS is outside the boundaries of the collar and the hedge has intrinsic value, the Company records a gain or loss for the change in the fair value of the hedged portion of Lionsgate shares that correspond to the change in intrinsic value of the hedge as a component of other (expense) income, net . (See Note 10.) In 2016 , the Company determined that the decline in value of AFS securities related to its investment in Lionsgate was other-than-temporary in nature and, as such, the cost basis was adjusted to fair value. The impairment determination was based on the sustained decline in the stock price of Lionsgate in relation to the purchase price and the prolonged length of time the fair value of the investment has been less than the carrying value. Based on the other-than-temporary impairment determination, unrealized pre-tax losses of $62 million previously recorded as a component of other comprehensive income (loss) were recognized as an impairment charge that is included as a component of other (expense) income, net for the year ended December 31, 2016 . Since the impairment charge in 2016 , the changes in fair value as result of changes in stock price have been recorded as a component of other comprehensive income (loss) . Cost Method Investments The Company's cost method investments as of December 31, 2017 and December 31, 2016 totaled $295 million and $245 million , respectively, and primarily include its non-controlling interest in Group Nine Media with a carrying value of $212 million and $182 million as of December 31, 2017 and December 31, 2016 , respectively. (See Note 3.) Although Discovery has significant influence through its voting rights in the preferred stock of Group Nine Media, the Company applied the cost method for its ownership interest, which does not meet the definition of in-substance common stock. As of December 31, 2017 , the Company owns a 42% minority interest in Group Nine Media. The Company increased its cost method investments by $50 million and $18 million for the years ended December 31, 2017 and December 31, 2016 . For the year ended December 31, 2017 , there were no indicators of impairment or that the fair values of the Company's investments had changed materially.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS Fair value is defined as the amount that would be received for selling an asset or paid to transfer a liability in an orderly transaction between market participants. Assets and liabilities carried at fair value are classified in the following three categories: Level 1 – Quoted prices for identical instruments in active markets. Level 2 – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets. Level 3 – Valuations derived from techniques in which one or more significant inputs are unobservable. The table below presents assets and liabilities measured at fair value on a recurring basis (in millions). December 31, 2017 Category Balance Sheet Location Level 1 Level 2 Level 3 Total Assets: Cash equivalent: Time deposits Cash and cash equivalents $ — $ 1,305 $ — $ 1,305 Trading securities: Money market funds Cash and cash equivalents 2,707 — — 2,707 Mutual funds Prepaid expenses and other current assets 182 — — 182 AFS securities: Common stock Other noncurrent assets 82 — — 82 Common stock - pledged Other noncurrent assets 82 — — 82 Derivatives: Cash flow hedges: Foreign exchange Prepaid expenses and other current assets — 7 — 7 Net investment hedges: Cross-currency swaps Other noncurrent assets — 3 — 3 Foreign exchange Prepaid expenses and other current assets — 2 — 2 Fair value hedges: Equity (Lionsgate Collar) Other noncurrent assets — 13 — 13 Total $ 3,053 $ 1,330 $ — $ 4,383 Liabilities: Deferred compensation plan Accrued liabilities $ 182 $ — $ — $ 182 Derivatives: Cash flow hedges: Foreign exchange Accrued liabilities — 12 — 12 Net investment hedges: Cross-currency swaps Accrued liabilities — 13 — 13 Cross-currency swaps Other noncurrent liabilities — 98 — 98 Foreign exchange Accrued liabilities — 8 — 8 No hedging designation: Credit contracts Other noncurrent liabilities — 1 — 1 Cross-currency swaps Other noncurrent liabilities — 6 — 6 Total $ 182 $ 138 $ — $ 320 December 31, 2016 Category Balance Sheet Location Level 1 Level 2 Level 3 Total Assets: Trading securities - mutual funds Prepaid expenses and other current assets $ 160 $ — $ — $ 160 Available-for-sale securities: Common stock Other noncurrent assets 64 — — 64 Common stock - pledged Other noncurrent assets 64 — — 64 Derivatives: Cash flow hedges: Foreign exchange Prepaid expenses and other current assets — 31 — 31 Net investment hedges: Cross-currency swaps Other noncurrent assets — 35 — 35 Fair value hedges: Equity (Lionsgate Collar) Other noncurrent assets — 25 — 25 No hedging designation: Cross-currency swaps Other noncurrent assets — 1 — 1 Total $ 288 $ 92 $ — $ 380 Liabilities: Deferred compensation plan Accrued liabilities $ 160 $ — $ — $ 160 Derivatives: Cash flow hedges: Foreign exchange Accrued liabilities — 18 — 18 Net investment hedges: Cross-currency swaps Accrued liabilities — 3 — 3 Cross-currency swaps Other noncurrent liabilities — 31 — 31 Total $ 160 $ 52 $ — $ 212 Cash obtained as a result of the issuance of senior notes to fund a portion of the purchase price of the Scripps Networks acquisition is invested into money market funds, time deposit accounts, U.S. Treasury securities and highly liquid short-term instruments that qualify as cash and cash equivalents. Any accrued interest received after maturity are reinvested into additional short-term instruments. (See Note 4.) The Company values cash and cash equivalents using quoted market prices. The fair value of Level 1 trading securities was determined by reference to the quoted market price per unit in active markets multiplied by the number of units held without consideration of transaction costs. (See Note 4.) The fair value of the deferred compensation plan liability was determined based on the fair value of the related investments elected by employees. AFS securities represent equity investments with readily determinable fair values. The fair value of Level 1 AFS securities was determined by reference to the quoted market price per unit in active markets multiplied by the number of units held without consideration of transaction costs. (See Note 4.) Derivative financial instruments are comprised of foreign exchange, interest rate, credit and equity contracts. (See Note 10). The fair value of Level 2 derivative financial instruments was determined using a market-based approach. In addition to the financial instruments listed in the tables above, the Company has other financial instruments, including cash deposits, accounts receivable, accounts payable, commercial paper, borrowings under the revolving credit facility, capital leases and senior notes. The carrying values for such financial instruments, other than senior notes, each approximated their fair values as of December 31, 2017 and December 31, 2016 . The estimated fair value of the Company’s outstanding senior notes using quoted prices from over the counter markets, considered Level 2 inputs, was $14.8 billion and $7.4 billion as of December 31, 2017 and 2016 , respectively.

Content Rights

Content Rights	12 Months Ended
	Dec. 31, 2017
Content Rights [Abstract]
Content Rights	CONTENT RIGHTS The following table presents the components of content rights (in millions). December 31, 2017 2016 Produced content rights: Completed $ 4,355 $ 3,920 In-production 442 420 Coproduced content rights: Completed 745 632 In-production 27 57 Licensed content rights: Acquired 1,070 1,090 Prepaid (a) 181 129 Content rights, at cost 6,820 6,248 Accumulated amortization (4,197 ) (3,849 ) Total content rights, net 2,623 2,399 Current portion (410 ) (310 ) Noncurrent portion $ 2,213 $ 2,089 (a) Prepaid licensed content rights includes prepaid rights to the Olympic Games of $83 million that are reflected as current content rights assets on the consolidated balance sheet as of December 31, 2017 . Content expense is included in costs of revenues on the consolidated statements of operations and consisted of the following (in millions). For the year ended December 31, 2017 2016 2015 Content amortization $ 1,878 $ 1,701 $ 1,628 Other production charges 310 272 231 Content impairments (a) 32 72 81 Total content expense $ 2,220 $ 2,045 $ 1,940 (a) Content impairments are generally recorded as a component of costs of revenue. However during the years ended December 31, 2016 and 2015 , content impairments of $7 million and $21 million , respectively, were reflected as a component of restructuring and other charges. These impairment charges resulted from the cancellation of certain series due to legal circumstances pertaining to the associated talent. No content impairments were recorded as a component of restructuring and other during the year ended December 31, 2017 . As of December 31, 2017 , the Company estimates that approximately 96% of unamortized costs of content rights, excluding content in-production and prepaid licenses, will be amortized within the next three years. As of December 31, 2017 , the Company will amortize $1.1 billion of the above unamortized content rights, excluding content in-production and prepaid licenses, during the next twelve months.

Property And Equipment

Property And Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property And Equipment	PROPERTY AND EQUIPMENT Property and equipment consisted of the following (in millions). December 31, 2017 2016 Land, buildings and leasehold improvements $ 363 $ 327 Broadcast equipment 728 607 Capitalized software costs 379 347 Office equipment, furniture, fixtures and other 431 333 Property and equipment, at cost 1,901 1,614 Accumulated depreciation (1,304 ) (1,132 ) Property and equipment, net $ 597 $ 482 Property and equipment includes assets acquired under capital lease arrangements, primarily satellite transponders classified as broadcast equipment, with gross carrying values of $358 million and $284 million as of December 31, 2017 and 2016 , respectively. The related accumulated amortization for capital lease assets was $154 million and $155 million as of December 31, 2017 and 2016 , respectively. The net book value of capitalized software costs was $86 million and $96 million as of December 31, 2017 and 2016 , respectively. Depreciation expense for property and equipment, including amortization of capitalized software costs and capital lease assets, totaled $150 million , $139 million and $138 million for 2017 , 2016 and 2015 , respectively. In addition to the capitalized property and equipment included in the above table, the Company rents certain facilities and equipment under operating lease arrangements. Rental expense for operating leases totaled $127 million , $122 million and $134 million for 2017 , 2016 and 2015 , respectively.

Goodwill And Intangible Assets

Goodwill And Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill And Intangible Assets	GOODWILL AND INTANGIBLE ASSETS Goodwill The carrying value and changes in the carrying value of goodwill attributable to each business unit were as follows (in millions). U.S. Networks International Networks Education and Other Total December 31, 2015 $ 5,287 $ 2,800 $ 77 $ 8,164 Dispositions (Note 3) (22 ) — — (22 ) Foreign currency translation — (92 ) (10 ) (102 ) December 31, 2016 5,265 2,708 67 8,040 Acquisitions (Note 3) 211 7 — 218 Dispositions (Note 3) — — (30 ) (30 ) Impairment of goodwill — (1,327 ) — (1,327 ) Foreign currency translation 2 167 3 172 December 31, 2017 $ 5,478 $ 1,555 $ 40 $ 7,073 The carrying amount of goodwill at the International Networks segment included accumulated impairments of $1.3 billion as of December 31, 2017 . The carrying amount of goodwill at the U.S. Networks segment included accumulated impairments of $20 million as of December 31, 2017, 2016 and 2015, respectively. Intangible Assets Finite-lived intangible assets consisted of the following (in millions, except years). Weighted Average Amortization Period (Years) December 31, 2017 December 31, 2016 Gross Accumulated Amortization Net Gross Accumulated Amortization Net Intangible assets subject to amortization: Trademarks 10 $ 494 $ (224 ) $ 270 $ 412 $ (165 ) $ 247 Customer relationships 16 2,026 (758 ) 1,268 1,632 (594 ) 1,038 Other 16 118 (50 ) 68 97 (34 ) 63 Total $ 2,638 $ (1,032 ) $ 1,606 $ 2,141 $ (793 ) $ 1,348 Indefinite-lived intangible assets not subject to amortization (in millions): December 31, 2017 2016 Intangible assets not subject to amortization: Trademarks $ 164 $ 164 Straight-line amortization expense for finite-lived intangible assets reflects the pattern in which the assets' economic benefits are consumed over their estimated useful lives. Amortization expense related to finite-lived intangible assets was $180 million , $183 million and $192 million for 2017 , 2016 and 2015 , respectively. Amortization expense relating to intangible assets subject to amortization for each of the next five years and thereafter is estimated to be as follows (in millions). 2018 2019 2020 2021 2022 Thereafter Amortization expense $ 220 $ 203 $ 198 $ 174 $ 147 $ 664 The amount and timing of the estimated expenses in the above table may vary due to future acquisitions, dispositions, impairments, changes in estimated useful lives or changes in foreign currency exchange rates. Impairment Analysis Consistent with the Company's accounting policy, the Company performed a quantitative step 1 impairment test (comparison of fair value to carrying value) for each of its reporting units in 2016 which indicated limited headroom (the excess of fair value over carrying value) in the European reporting unit of 12% , all other reporting units had headroom in excess of 40% . Given the limited headroom in the European reporting unit, the Company closely monitored its results during 2017 and again performed a quantitative impairment test of the European reporting unit as of November 30, 2017 , which indicated potential impairment (approximately $100 million or 3% deficit). The key factors resulting in the impairment include: 1) moderated revenue expectations based on continued declines in viewership, 2) expected increases in content investment to service existing customers and grow the Company's direct-to-consumer business, and 3) lower stock price multiples for peer media companies. Given the results of the step 1 impairment test, the Company applied the hypothetical purchase price analysis required by the step 2 test and recognized a pre-tax goodwill impairment charge of $1.3 billion as of November 30, 2017 , for the European reporting unit. The impairment charge of $1.3 billion significantly exceeds the deficit of fair value to carrying value of approximately $100 million because of significant intangible assets that are not recognized on the Company's consolidated balance sheet (i.e., excluded from book carrying value) but are considered in the step 2 calculation on a fair value basis. The step 1 and step 2 tests and relevant assumptions are further discussed below. For the US Networks, Latin, Asia and Education reporting units, the Company performed a qualitative goodwill impairment review in 2017. No factors were identified indicating a need for a quantitative assessment. For the 2017 step 1 test, the carrying value of the European reporting unit of $4.0 billion , which includes $2.4 billion of goodwill, exceeded its fair value of $3.9 billion by 3% . In performing the step 1 test, the Company determined the fair value of its European reporting unit by using a combination of DCF analyses and market-based valuation methodologies. The results of these valuation methodologies were weighted 75% towards the DCF and 25% towards the market-based approach, which is consistent with prior quantitative analyses. Significant judgments and assumptions used in the DCF and market-based model to assess the reporting unit's fair value include the amount and timing of expected future cash flows, long-term growth rates of 2.5% (compared with 3% in 2016 ), a discount rate of 9.75% (compared with 10.5% in 2016 ), and our selection of guideline company earnings multiples of 7.5 (compared with 9.5 in 2016). The cash flows employed in the DCF analysis for the European reporting unit are based on the reporting unit's budget and long-term business plan, which reflect our expectations based upon recent operating performance. Discount rate assumptions are based on an assessment of the risk inherent in the future cash flows of the respective reporting unit and market conditions. Given the inherent uncertainty in determining the assumptions underlying a DCF analysis, actual results may differ from those used in the valuations. The net assets assigned to the European reporting unit included corporate allocations. These assets and liabilities include corporate enterprise goodwill and intangible assets, allocated in prior periods based on the relative fair value of the European reporting unit at the time, and deferred taxes and content, allocated based on whether or not the jurisdiction gave rise to the deferred tax balance or is using the content asset. In the second step of the impairment test, the Company hypothetically assigned the European reporting unit's fair value to its individual assets and liabilities, including significant unrecognized intangible assets such as customer relationships and trade names, or liabilities, in a hypothetical purchase price allocation that calculates the implied fair value of goodwill in the same manner as if the reporting unit was being acquired in a business combination. Since the implied fair value of the reporting unit's goodwill was less than the carrying value, the difference was recorded as an impairment charge. The fair value estimates incorporated in step 2 for the hypothetical intangible assets were based on the excess earnings income approach for customer relationships, the relief-from-royalty method for trademarks, and the greenfield approach for broadcast licenses. Key judgments made by management in step 2 of the impairment test included revenue growth rates, length of contract term, number of renewals, customer attrition rates, market-based royalty rates, and market based tax rates. The valuation of advertising relationships assumed an attrition rate of 10% , affiliate relationships assumed three contract renewals, each with a four year term, per customer and trade names assumed royalty rates ranging from 2% to 5% . Other assumptions used in these hypothetical calculations had a less significant impact on the concluded fair value or were subject to less significant estimation or judgment. None of these hypothetical calculations for unrecorded intangibles were recorded in the consolidated financial statements. As of the goodwill testing date, the carrying value of remaining goodwill assigned to the European reporting unit was $1.1 billion and the net assets of the reporting unit were approximately $2.7 billion , which results in $1.2 billion headroom based on the estimated fair value of $3.9 billion . The determination of fair value of the Company's DNI-Europe reporting unit represents a Level 3 fair value measurement in the fair value hierarchy due to its use of internal projections and unobservable measurement inputs. Changes in significant judgments and estimates could significantly impact the concluded fair value of the reporting unit or the valuation of intangible assets. Changes to assumptions that would decrease the fair value of the reporting unit would result in corresponding increases to the impairment of goodwill at the reporting unit. The goodwill impairment charge does not have an impact on the calculation of the Company's financial covenants under the Company's debt arrangements. As of November 30, 2016 , the Company performed a quantitative goodwill impairment assessment for all reporting units. Due to the period elapsed since the last quantitative impairment test in 2013, the Company elected to proceed to the first step of the quantitative goodwill impairment test. The estimated fair value of each reporting unit exceeded its carrying value and, therefore, no impairment was recorded. The fair values of the reporting units were determined using DCF and market-based valuation models. Cash flows were determined based on Company estimates of future operating results and discounted using an internal rate of return based on an assessment of the risk inherent in future cash flows of the respective reporting unit. The market-based valuation models utilized multiples of earnings before interest, taxes, depreciation and amortization. Both the DCF and market-based models resulted in substantially similar fair values. As of November 30, 2015 , the Company performed a qualitative goodwill impairment assessment for all reporting units, and determined that it was more likely than not that the fair value of those reporting units exceeded their carrying values.

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	DEBT The table below presents the components of outstanding debt (in millions). December 31, 2017 2016 5.625% Senior notes, semi-annual interest, due August 2019 $ 411 $ 500 2.200% Senior notes, semi-annual interest, due September 2019 500 — Floating rate notes, quarterly interest, due September 2019 400 — 5.050% Senior notes, semi-annual interest, due June 2020 789 1,300 4.375% Senior notes, semi-annual interest, due June 2021 650 650 2.375% Senior notes, euro denominated, annual interest, due March 2022 358 314 3.300% Senior notes, semi-annual interest, due May 2022 500 500 2.950% Senior notes, semi-annual interest, due March 2023 1,200 — 3.250% Senior notes, semi-annual interest, due April 2023 350 350 3.800% Senior notes, semi-annual interest, due March 2024 450 — 2.500% Senior notes, sterling denominated, annual interest, due September 2024 538 — 3.450% Senior notes, semi-annual interest, due March 2025 300 300 4.900% Senior notes, semi-annual interest, due March 2026 700 500 1.900% Senior notes, euro denominated, annual interest, due March 2027 717 627 3.950% Senior notes, semi-annual interest, due March 2028 1,700 — 5.000% Senior notes, semi-annual interest, due September 2037 1,250 — 6.350% Senior notes, semi-annual interest, due June 2040 850 850 4.950% Senior notes, semi-annual interest, due May 2042 500 500 4.875% Senior notes, semi-annual interest, due April 2043 850 850 5.200% Senior notes, semi-annual interest, due September 2047 1,250 — Revolving credit facility 425 550 Commercial paper — 48 Capital lease obligations 225 151 Total debt 14,913 7,990 Unamortized discount and debt issuance costs (128 ) (67 ) Debt, net 14,785 7,923 Current portion of debt (30 ) (82 ) Noncurrent portion of debt $ 14,755 $ 7,841 Senior Notes On September 21, 2017 , Discovery Communications, LLC ("DCL"), a wholly-owned subsidiary of the Company, issued $500 million principal amount of 2.200% senior notes due 2019 (the “2019 Notes”), $1.20 billion principal amount of 2.950% senior notes due 2023 (the “2023 Notes”), $1.70 billion principal amount of 3.950% senior notes due 2028 (the “2028 Notes”), $1.25 billion principal amount of 5.000% senior notes due 2037 (the “2037 Notes”), $1.25 billion principal amount of 5.200% senior notes due 2047 (the “2047 Notes” and, together with the 2019 Notes, the 2023 Notes, the 2028 Notes, the 2037 Notes and the 2047 Notes, the “Senior Fixed Rate Notes”) and $400 million principal amount of floating rate senior notes due 2019 (the “Senior Floating Rate Notes” and, together with the Senior Fixed Rate Notes, the “USD Notes”). Interest on the Senior Fixed Rate Notes is payable on March 20 and September 20 of each year, beginning March 20, 2018. Interest on the Senior Floating Rate Notes is payable on March 20, June 20, September 20 and December 20 of each year, beginning December 20, 2017. The USD Notes are fully and unconditionally guaranteed by the Company. On September 21, 2017 , DCL issued £400 million principal amount ( $540 million at issuance based on the exchange rate of $1.35 per pound at September 21, 2017) of 2.500% senior notes due 2024 (the “Sterling Notes”). Interest on the Sterling Notes is payable on September 20 of each year, beginning September 20, 2018. The proceeds received by DCL from the USD Notes and the Sterling Notes were net of a $11 million issuance discount and $57 million of debt issuance costs. The Sterling Notes are fully and unconditionally guaranteed by the Company. With the exception of the 2019 Notes and the Senior Floating Rate Notes, the USD Notes and Sterling Notes include a redemption requirement following a termination of the Scripps Networks Merger Agreement or if the merger does not close prior to August 30, 201 8. The $5.9 billion principal amount of senior notes subject to special mandatory redemption will be classified as noncurrent until either of the contingent events which would trigger the redemption has occurred. As of December 31, 2017 , neither of the contingent events have occurred and therefore these senior notes are classified as noncurrent. In the event that the redemption provision is triggered, the Company would be required to redeem the notes for a price equal to 101% of the principal amount plus any accrued and unpaid interest on the notes. On March 13, 2017 , DCL issued $ 450 million principal amount of 3.80% senior notes due March 13, 2024 (the "2017 USD Notes") and an additional $200 million principal amount of its existing 4.90% senior notes due March 11, 2026 (the "2016 USD Notes"). Interest on the 2017 USD Notes is payable semi-annually on March 13 and September 13 of each year. Interest on the 2016 USD Notes is payable semi-annually on March 11 and September 11 of each year. The proceeds received by DCL from the 2017 USD Notes were net of a $1 million issuance discount and $4 million of debt issuance costs. The proceeds received by DCL from the 2016 USD Notes included a $10 million issuance premium and were net of $2 million of debt issuance costs. The 2017 USD Notes and the 2016 USD Notes are fully and unconditionally guaranteed by the Company. DCL used the proceeds from the offerings of the 2017 USD Notes and the 2016 USD Notes to repurchase $600 million aggregate principal amount of DCL's 5.05% senior notes due 2020 and 5.625% senior notes due 2019 in a cash tender offer. The repurchase resulted in a pretax loss on extinguishment of debt of $54 million for the year ended December 31, 2017 , which is presented as a separate line item on the Company's consolidated statements of operations and recognized as a component of financing cash outflows on the consolidated statements of cash flows. The loss included $50 million for premiums to par value, $2 million of non-cash write-offs of unamortized deferred financing costs, $1 million for the write-off of the original issue discount of these senior notes and $1 million accrued for other third-party fees. Term Loans On August 11, 2017 , DCL entered into a three -year delayed draw tranche and a five -year delayed draw tranche unsecured term loan credit facility (the "Term Loans"), each with a principal amount of up to $1 billion . The term of each delayed draw loan begins when Discovery borrows the funds to finance a portion of the Scripps Networks acquisition. The Term Loans' interest rates are based, at the Company's option, on either adjusted LIBOR plus a margin, or an alternate base rate plus a margin. The Company will pay a commitment fee of 20 basis points per annum for each Term Loan, based on its current credit rating, beginning September 28, 2017 until either the funding of the Term Loans or the termination of the Scripps Networks acquisition. As of December 31, 2017 , the Company has not yet borrowed the Term Loans. Unsecured Bridge Loan Commitment On July 30, 2017 , the Company obtained a commitment letter from a financial institution for a $9.6 billion unsecured bridge term loan facility that could have been used to complete the Scripps Networks acquisition. No amounts were drawn under the bridge loan commitment and following the execution of the Term Loans and the issuance of the USD Notes and the Sterling Notes on September 21, 2017 , the commitment was terminated. The Company incurred $40 million of debt issuance costs, which are fully amortized as a component of interest expense following the issuance of the senior notes on September 21, 2017 . The associated cash payment has been classified as a financing activity in the consolidated statements of cash flows. Revolving Credit Facility On August 11, 2017 , DCL amended its $2.0 billion revolving credit facility to allow DCL and certain designated foreign subsidiaries of DCL to borrow up to $2.5 billion , including a $100 million sublimit for the issuance of standby letters of credit and a $50 million sublimit for Euro-denominated swing line loans. Borrowing capacity under this agreement is reduced by any outstanding borrowings under the commercial paper program discussed below. The revolving credit facility agreement amendment extends the maturity date from February 4, 2021 to August 11, 2022 , with the option for up to two additional 364 -day renewal periods. The amended credit facility agreement expressly permits the incurrence of indebtedness to finance the Scripps Networks acquisition. Discovery also agreed to make Scripps Networks a guarantor under the agreement following the closing of the acquisition. The credit agreement governing the revolving credit facility contains customary representations, warranties and events of default, as well as affirmative and negative covenants. In addition to the change in the revolver's capacity on August 11, 2017 , the financial covenants were modified to reset the maximum consolidated leverage ratio financial covenant to 5.50 to 1.00 , with step-downs to 5.00 to 1.00 and to 4.50 to 1.00 , one year and two years after the closing of the Scripps Networks acquisition, respectively. As of December 31, 2017 , the Company's subsidiary, DCL, was in compliance with all covenants and there were no events of default under the revolving credit facility. The following table presents a summary of the outstanding borrowings under the revolving credit facility (in millions). For the year ended December 31, 2017 2016 Outstanding debt $ 425 $ 550 Outstanding debt denominated in foreign currency — 207 Weighted average interest rate 2.69 % 2.05 % The interest rate on borrowings under the revolving credit facility is variable based on DCL's then-current credit ratings for its publicly traded debt and changes in financial index rates. For dollar-denominated borrowings, the interest rate is based, at the Company's option, on either adjusted LIBOR plus a margin, or an alternate base rate plus a margin. For borrowings denominated in foreign currencies, the interest rate is based on adjusted LIBOR, plus a margin. The current margins are 1.30% and 0.30% , respectively, per annum for adjusted LIBOR and alternate base rate borrowings. A monthly facility fee is charged based on the total capacity of the facility, and interest is charged based on the amount borrowed on the facility. The current facility fee rate is 0.20% per annum and subject to change based on DCL's then-current credit ratings. All obligations of DCL and the other borrowers under the revolving credit facility are unsecured and are fully and unconditionally guaranteed by Discovery. Commercial Paper The Company's commercial paper program is supported by the revolving credit facility described above. The following table presents a summary of the outstanding commercial paper borrowings with maturities of less than 90 days (in millions). For the year ended December 31, 2017 2016 Outstanding debt $ — $ 48 Weighted average interest rate — % 1.2 % Long-term Debt Repayment Schedule The following table presents a summary of scheduled and estimated debt payments, excluding the revolving credit facility, commercial paper borrowings and capital lease obligations, for the succeeding five years based on the amount of debt outstanding as of December 31, 2017 (in millions). 2018 2019 2020 2021 2022 Thereafter Long-term debt repayments $ — $ 1,311 $ 789 $ 650 $ 858 $ 10,655 Scheduled payments for capital lease obligations outstanding as of December 31, 2017 are disclosed in Note 20.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	DERIVATIVE FINANCIAL INSTRUMENTS The Company uses derivative financial instruments to modify its exposure to exogenous events and market risks from changes in foreign currency exchange rates, interest rates and the fair value of investments classified as AFS securities. At the inception of a derivative contract, the Company designates the derivative as one of four types based on the Company's intentions and belief as to its likely effectiveness as a hedge. These four types are: (i) a cash flow hedge, (ii) a net investment hedge, (iii) a fair value hedge, or (iv) an instrument with no hedging designation. The Company does not enter into or hold derivative financial instruments for speculative trading purposes. Cash Flow Hedges The Company designates foreign currency forward and option contracts as cash flow hedges to mitigate foreign currency risk arising from third-party revenue and inter-company licensing agreements. The Company also designates interest rate contracts used to hedge the pricing for certain senior notes as cash flow hedges. During the three months ended December 31, 2016, the Company terminated and settled its outstanding interest rate cash flow hedges which resulted in a $40 million pretax gain. As the hedges were considered to be effective and the forecasted transactions were considered probable of occurring, the gain remained in accumulated other comprehensive loss to be amortized as a reduction to interest expense over the term of the forecasted senior notes. The Company reclassified $17 million of the gains from accumulated other comprehensive loss to other (expense) income, net , in the Company's consolidated statement of operations, as the forecasted transaction was considered remote following the issuance of the USD Notes on September 21, 2017. In 2016, the Company also discontinued hedge accounting for certain foreign currency forward and option cash flow hedges with notional and fair value amounts of $125 million and $14 million , respectively. At that time, the occurrence of the forecasted intercompany transactions was no longer considered probable, but was still reasonably possible of occurring. The change in probability was the result of new tax regulations that impacted the planned intercompany transactions that were hedged. As a result of the change in probability, subsequent changes in the fair value of these hedges were reflected immediately in other (expense) income, net on the consolidated statements of operations. The result was a $1 million gain recognized on the consolidated statements of operations for the period until November 1, 2016, when the forecasted transactions were once again considered probable, as it was determined that no changes to the forecasted intercompany transactions would occur. Accordingly, any changes in the fair value of these hedges subsequent to that date will remain in accumulated other comprehensive loss until earnings are impacted by the forecasted transaction, at which time they will be reclassified to other (expense) income, net on the consolidated statements of operations. In 2015, the Company terminated and settled its interest rate cash flow hedges following the pricing of its 3.45% senior notes due March 15, 2025 (the "2015 USD Notes"). The total notional value of the interest rate forward contracts at the termination date was $490 million , which exceeded the $300 million principal amount of the 2015 USD Notes. Of the $40 million pretax loss recorded in accumulated other comprehensive loss at the termination date, $29 million was an effective cash flow hedge that will be amortized as an adjustment to interest expense over the ten year term of the 2015 USD Notes consistent with amortization of the debt discount. The remaining $11 million was reclassified into other (expense) income, net on the consolidated statements of operations during the year ended December 31, 2015, because the forecasted borrowing transaction was no longer probable. Net Investment Hedges The Company designates cross-currency swaps and foreign currency forward contracts as hedges of net investments in foreign operations. Changes in the fair value of these instruments, including the accrual and periodic cash settlement of interest on cross-currency swaps, are reported in the same manner as translation adjustments to the extent that they are effective. Changes in the value of the investment due to changes in spot rates are offset by fair value changes in the effective portion of the derivative instruments. On September 21, 2017, in conjunction with the Scripps Networks acquisition (see Note 3 and Note 9), DCL issued £400 million principal amount of 2.500% senior notes due 2024. The Sterling Notes were designated as net investment hedges, hedging against fluctuations in foreign currency exchange rates on a portion of the Company's investments in foreign subsidiaries. Prior to issuance of the Sterling Notes, the Company also entered into a series of foreign exchange contracts designated as net investment hedges on a portion of the Company's investments in foreign subsidiaries. These foreign exchange contracts were settled on the date of issuance of the Sterling Notes and resulted in a $12 million loss, which has been reflected as a component of currency translation adjustments on the Company's consolidated balance sheet as of December 31, 2017 . Fair Value Hedges The Company designates derivative instruments used to mitigate the risk of changes in the fair value of its AFS securities as fair value hedges. On November 12, 2015, the Company entered into the Lionsgate Collar, designed to mitigate the risk of market fluctuations with respect to 50% of the Lionsgate shares held by the Company. (See Note 4.) The collar, which qualifies for hedge accounting, settles in three tranches starting in 2019 and ending in 2022. No Hedging Designation The Company may also enter into derivative financial instruments that do not qualify for hedge accounting and are not designated as hedges. These instruments are intended to mitigate economic exposures due to exogenous events and changes in foreign currency exchange rates and interest rates. During the three months ended September 30, 2017, in conjunction with the Scripps Networks acquisition (see Note 3 and Note 9), the Company entered into $4 billion notional amount of interest rate contracts used to economically hedge a portion of the pricing of the 2017 USD Notes. These interest rate contracts were settled on September 21, 2017 , and did not receive hedging designation. The Company recognized a $98 million loss in connection with these interest rate contracts, which has been reflected as a component of other (expense) income, net on the Company's consolidated statement of operations. Financial Statement Presentation The Company records all unsettled derivative contracts at their gross fair values on the consolidated balance sheets. (See Note 5.) The portion of the fair value that represents cash flows occurring within one year are classified as current, and the portion related to cash flows occurring beyond one year are classified as noncurrent. The following table summarizes the impact of derivative financial instruments on the Company's consolidated balance sheets (in millions). There were no amounts eligible to be offset under master netting agreements as of December 31, 2017 and December 31, 2016 . December 31, 2017 December 31, 2016 Fair Value Fair Value Notional Prepaid expenses and other current assets Other non- current assets Accrued liabilities Other non- current liabilities Notional Prepaid expenses and other current assets Other non- current assets Accrued liabilities Other non- current liabilities Cash flow hedges: Foreign exchange $ 817 $ 7 $ — $ 12 $ — $ 677 $ 31 $ — $ 18 $ — Net investment hedges: (a) Cross-currency swaps 1,708 — 3 13 98 751 — 35 3 31 Foreign exchange 303 2 — 8 — — — — — — Fair value hedges: Equity (Lionsgate collar) 97 — 13 — — 97 — 25 — — No hedging designation: Interest rate swaps 25 — — — — 25 — — — — Cross-currency swaps 64 — — — 6 64 — 1 — — Credit contracts 665 — — — 1 — — — — — Total $ 9 $ 16 $ 33 $ 105 $ 31 $ 61 $ 21 $ 31 (a) Excludes £400 million of sterling notes ( $538 million equivalent at December 31, 2017 ) designated as a net investment hedge. (Note 9.) The following table presents the pretax impact of derivatives designated as cash flow hedges on income and other comprehensive income (loss) (in millions). Year Ended December 31, 2017 2016 2015 (Losses) gains recognized in accumulated other comprehensive loss: Foreign exchange - derivative adjustments $ (41 ) $ (1 ) $ 34 Interest rate swaps - derivative adjustments — 40 (11 ) (Losses) gains reclassified into income from accumulated other comprehensive loss (effective portion): Foreign exchange - distribution revenue (22 ) (25 ) 23 Foreign exchange - advertising revenue (3 ) (2 ) 2 Foreign exchange - costs of revenues — 27 9 Foreign exchange - other (expense) income, net — 3 4 Interest rate - interest expense (1 ) (3 ) (3 ) Gains (losses) reclassified into income from accumulated other comprehensive loss (ineffective portion): Foreign exchange - other (expense) income, net — 1 — Interest rate - other (expense) income, net 17 — (11 ) Fair value excluded from effectiveness assessment: Foreign exchange - other (expense) income, net — (5 ) — If current fair values of designated cash flow hedges as of December 31, 2017 remained static over the next twelve months, the Company would reclassify $6 million of net deferred losses from accumulated other comprehensive loss into income in the next twelve months. The following table presents the pretax impact of derivatives designated as net investment hedges on other comprehensive income (loss) (in millions). Year Ended December 31, 2017 2016 2015 Currency translation adjustments: Cross-currency swaps - changes in fair value $ (109 ) $ 1 $ — Cross-currency swaps - interest settlements 13 2 — Foreign exchange - changes in fair value (18 ) — — Sterling Notes - changes in foreign exchange rates 2 — — Total in other comprehensive income (loss) $ (112 ) $ 3 $ — The following table presents the pretax impact of derivatives designated as fair value hedges on income, including offsetting changes in fair value of the hedged items and amounts excluded from the assessment of effectiveness (in millions). The Company recognized $1 million of ineffectiveness on fair value hedges for the years ended December 31, 2017 and 2016 . Year Ended December 31, 2017 2016 2015 Gains (losses) on changes in fair value of hedged AFS $ 18 $ (17 ) $ (2 ) (Losses) gains on changes in the intrinsic value of equity contracts (17 ) 16 2 Fair value of equity contracts excluded from effectiveness assessment 5 (6 ) 10 Total in other (expense) income, net $ 6 $ (7 ) $ 10 The following table presents the pretax (losses) gains on derivatives not designated as hedges and recognized in other (expense) income, net in the consolidated statements of operations (in millions). Year Ended December 31, 2017 2016 2015 Interest rate swaps $ (98 ) $ — $ — Cross-currency swaps (6 ) — — Foreign exchange — (1 ) 6 Credit contracts (1 ) — — Total in other (expense) income, net $ (105 ) $ (1 ) $ 6

Redeemable Noncontrolling Inter

Redeemable Noncontrolling Interest	12 Months Ended
	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Redeemable Noncontrolling Interest	REDEEMABLE NONCONTROLLING INTERESTS Redeemable noncontrolling interests reflected as of the balance sheet date are the greater of the noncontrolling interest balances adjusted for comprehensive income items and distributions or the redemption values including any remeasurement necessary at the period end foreign exchange rates (i.e., the "floor"). Adjustments to the carrying amount of redeemable noncontrolling interests to redemption value as a result of changes in exchange rates are reflected in currency translation adjustments, a component of other comprehensive income (loss) ; however, such currency translation adjustments to redemption value are allocated to Discovery stockholders only. Redeemable noncontrolling interest adjustments of redemption value to the floor are reflected in retained earnings. Any adjustment of redemption value to the floor that reflects a redemption in excess of fair value is included as an adjustment to net (loss) income available to Discovery stockholders in the calculation of earnings per share. There were no current period adjustments to reflect a redemption in excess of fair value. (See Note 17.) The table below presents the reconciliation of changes in redeemable noncontrolling interests (in millions). December 31, 2017 2016 2015 Beginning balance $ 243 $ 241 $ 747 Initial fair value of redeemable noncontrolling interests of acquired businesses 137 — 60 Purchase of subsidiary shares at fair value — — (551 ) Cash distributions to redeemable noncontrolling interests (30 ) (22 ) (42 ) Comprehensive (loss) income adjustments: Net income attributable to redeemable noncontrolling interests 24 23 13 Other comprehensive income (loss) attributable to redeemable noncontrolling interests 1 — (23 ) Currency translation on redemption values — 1 (36 ) Retained earnings adjustments: Adjustments to redemption value 38 — 73 Ending balance $ 413 $ 243 $ 241 Redeemable noncontrolling interests consist of the arrangements described below: On November 30, 2017, the Company acquired from Harpo a controlling interest in OWN, increasing Discovery’s ownership stake from 49.50% to 73.99% . Harpo has the right to require the Company to purchase its remaining non-controlling interest during 90-day windows beginning on July 1, 2018 and every two and half years thereafter through January 1, 2026. As OWN’s put right is outside the control of the Company, OWN’s noncontrolling interest is presented as redeemable noncontrolling interest outside of permanent equity on the Company's consolidated balance sheet. The Company recorded $55 million for the value of the put right for OWN. (See Note 3.) In connection with the joint venture created between Discovery and GoldenTree on September 25, 2017 , GoldenTree acquired a put right exercisable during 30 day windows beginning in March 2021, September 2022 and March 2024 that requires Discovery to either purchase all of GoldenTree's 32.5% interest in the joint venture at fair value or participate in an initial public offering for the joint venture. As the put right is outside of the Company's control, GoldenTree's 32.5% noncontrolling interest is presented as redeemable noncontrolling interest outside of permanent equity on the Company's consolidated balance sheet. The Company recorded a redeemable noncontrolling interest of $82 million and an adjustment to redemption value of $38 million for the value of the put right for VTEN. (See Note 3.) In connection with its non-controlling interest in Discovery Family, Hasbro has the right to put the entirety of its remaining 40% non-controlling interest to the Company for one year after December 31, 202 1, or in the event a Discovery performance obligation related to Discovery Family is not met. Embedded in the redeemable noncontrolling interest is also a Discovery call right that is exercisable for one year after December 31, 2021 . Upon the exercise of the put or call options, the price to be paid for the redeemable noncontrolling interest is a function of the then current fair market value of the redeemable noncontrolling interest, to which certain discounts and floor values may apply in specified situations depending upon the party exercising the put or call and the basis for the exercise of the put or call. As Hasbro's put right is outside the control of the Company, Hasbro's 40% noncontrolling interest is presented as redeemable noncontrolling interest outside of permanent equity on the Company's consolidated balance sheet. The Company recorded $210 million for the value of the put right for Discovery Family. In connection with its non-controlling interest in Discovery Japan, Jupiter Telecommunications Co., Ltd ("J:COM") has the right to put all, but not less than all, of its 20% noncontrolling interest to Discovery at any time for cash. As amended, through January 10, 2018, the redemption value is the January 10, 2013 , fair value denominated in Japanese yen; thereafter, as chosen by J:COM, the redemption value is the then-current fair value or the January 10, 2013 , fair value denominated in Japanese yen. The Company recorded $27 million for the value of the put right for Discovery Japan. In connection with the acquisition of a controlling interest in Eurosport France on March 31, 2015 and Eurosport International on May 30, 2014 , the Company recognized $60 million and $ 558 million , respectively, for TF1's 49% redeemable noncontrolling interest in each entity. On July 22, 2015, TF1 exercised its right to put the entirety of its remaining 49% noncontrolling interest in both Eurosport France and Eurosport International to the Company for €491 million ( $551 million as of the date redemption became mandatory, and $548 million on October 1, 2015 when the transaction closed). The difference between the carrying amount of the redeemable noncontrolling interest and its fair value at the date of exercise resulted in a €25 million ( $28 million ) adjustment to retained earnings, recognized as a component of redeemable noncontrolling interest adjustments to redemption value on the consolidated statements of equity for the year ended December 31, 2016 . Upon acquisition of TF1's noncontrolling interest on October 1, 2015 , the Company adjusted the accumulated other comprehensive income balance of $61 million attributable to TF1 and allocated it to Discovery stockholders.

Equity

Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Equity	EQUITY Common Stock The Company has three series of common stock authorized, issued and outstanding as of December 31, 2017 : Series A common stock, Series B common stock and Series C common stock. Holders of these three series of common stock have equal rights, powers and privileges, except as otherwise noted. Holders of Series A common stock are entitled to one vote per share and holders of Series B common stock are entitled to ten votes per share on all matters voted on by stockholders, except for directors to be elected by holders of the Company’s Series A-1 convertible preferred stock. Holders of Series C common stock are not entitled to any voting rights, except as required by Delaware law. Generally, holders of Series A common stock and Series B common stock and Series A-1 convertible preferred stock vote as one class, except for certain preferential rights afforded to holders of Series A-1 convertible preferred stock. Holders of Series A common stock, Series B common stock and Series C common stock will participate equally in cash dividends if declared by the Board of Directors, subject to preferential rights of outstanding preferred stock. Each share of Series B common stock is convertible, at the option of the holder, into one share of Series A common stock. Series A and Series C common stock are not convertible. Generally, distributions made in shares of Series A common stock, Series B common stock or Series C common stock will be made proportionally to all common stockholders. In the event of a reclassification, subdivision or combination of any series of common stock, the shares of the other series of common stock will be equally reclassified, subdivided or combined. In the event of a liquidation, dissolution or winding up of Discovery, after payment of Discovery’s debts and liabilities and subject to preferential rights of outstanding preferred stock, holders of Series A common stock, Series B common stock and Series C common stock and holders of Series A-1 and Series C-1 convertible preferred stock will share equally in any assets available for distribution to holders of common stock. On February 13, 2014 , John C. Malone, a member of Discovery’s Board of Directors, entered into an agreement granting David Zaslav, the Company’s President and CEO, certain voting and purchase rights with respect to the approximately 6 million shares of the Company’s Series B common stock owned by Mr. Malone. The agreement gives Mr. Zaslav the right to vote the Series B shares if Mr. Malone is not otherwise voting or directing the vote of those shares. The agreement also provides that if Mr. Malone proposes to sell the Series B shares, Mr. Zaslav will have the first right to negotiate for the purchase of the shares. If that negotiation is not successful and Mr. Malone proposes to sell the Series B shares to a third party, Mr. Zaslav will have the exclusive right to match that offer. The rights granted under the agreement will remain in effect for as long as Mr. Zaslav is either employed as the principal executive officer of the Company or serving on its Board of Directors. Common Stock Repurchase Program Under the Company's stock repurchase program, management was authorized to purchase shares of the Company's common stock from time to time through open market purchases, privately negotiated transactions at prevailing prices, pursuant to one or more accelerated stock repurchase agreements, or other derivative arrangements as permitted by securities laws and other legal requirements, and subject to stock price, business and market conditions and other factors. The Company's authorization under the program expired on October 8, 2017 . All common stock repurchases, including prepaid common stock repurchase contracts, during 2017 , 2016 and 2015 were made through open market transactions. As of December 31, 2017 , the Company had repurchased over the life of the program 3 million and 164 million shares of Series A and Series C common stock, respectively, for the aggregate purchase price of $171 million and $6.6 billion , respectively. The table below presents a summary of common stock repurchases (in millions). Year Ended December 31, 2017 2016 2015 Series C Common Stock: Shares repurchased 14.3 34.8 23.7 Purchase price (a) $ 381 $ 895 $ 698 (a) The purchase price for Series C common stock in 2016 includes repurchases made pursuant to a common stock repurchase contract that was executed on August 22, 2016 and settled on December 2, 2016 at a cost of $71 million , resulting in the receipt of 2.8 million shares of Series C common stock at the then current market price equal to $75 million . See below for additional details. Convertible Preferred Stock and Preferred Stock Modification The Company has two series of preferred stock authorized, issued and outstanding as of December 31, 2017 : Series A-1 convertible preferred stock and Series C-1 convertible preferred stock. There are 8 million shares authorized for Series A-1 convertible preferred stock and 6 million shares authorized for Series C-1 convertible preferred stock. On August 7, 2017 , Discovery completed the transactions contemplated by the Exchange Agreement with Advance/Newhouse. Under the Exchange Agreement, Discovery issued a number of shares of newly designated Series A-1 and Series C-1 convertible preferred stock (collectively, the "New Preferred Stock") to Advance/Newhouse in exchange for all outstanding shares of Discovery Series A and Series C convertible participating preferred stock (the "Exchange"). The terms of the Exchange Agreement resulted in Advance/Newhouse's aggregate voting and economic rights before the exchange being equal to its aggregate voting and economic rights after the exchange. Immediately following the Exchange, Advance/Newhouse’s beneficial ownership of the aggregate number of shares of Discovery’s Series A common stock and Series C common stock into which the New Preferred Stock received by Advance/Newhouse in the Exchange are convertible, remained unchanged. The terms of the exchange agreement also provide that certain of the shares of Discovery Series C-1 convertible preferred stock received by Advance/Newhouse in the Exchange (including the Discovery Series C common stock into which such shares are convertible) are subject to transfer restrictions on the terms set forth in the Exchange Agreement. While subject to transfer restrictions, such shares may be pledged in certain bona fide financing transactions, but may not be pledged in connection with hedging or similar transactions. The following table summarizes the preferred shares issued at the time of the Exchange. Pre-Exchange Post-Exchange Shares Held Prior to the Amendment Converts into Common Stock Shares Issued Subsequent to the Amendment Converts into Common Stock Series A Preferred Stock 70,673,242 Common A 70,673,242 Series A-1 Preferred Stock 7,852,582 Common A 70,673,242 Common C 70,673,242 Series C-1 Preferred Stock 3,649,573 Common C 70,673,242 Series C Preferred Stock 24,874,370 Common C 49,748,740 Series C-1 Preferred Stock 2,569,020 Common C 49,748,740 Prior to the Exchange the Series A preferred stock had a carrying value of $108 million as a class of securities and each share of Series A preferred stock was convertible into one share of Series A common stock and one share of Series C common stock (referred to as the “embedded Series C common stock”). Through its ownership of the Series A convertible preferred stock, Advance/Newhouse had the right to elect three directors (the “preferred directors”) and maintained special voting rights on certain matters, including but not limited to blocking rights for material acquisitions, the issuance of debt securities and the issuance of equity securities (collectively, the “preferred rights”). Additionally, Advance/Newhouse was subject to certain transfer restrictions with respect to its governance rights. Prior to the Exchange, the Series C convertible preferred stock was considered the economic equivalent of Series C common stock. Following the Exchange, shares of Series A-1 preferred stock and Series C-1 preferred stock are convertible into Series A common stock and Series C common stock, respectively. The aforementioned preferred rights and transfer restrictions are retained as features of the Series A-1 convertible preferred stock, and holder of Series A-1 convertible preferred stock are now subject to a right of first offer in favor of Discovery should Advance/Newhouse desire to sell 80% or more of such shares in a “Permitted Transfer” (as defined in the Discovery charter). Following the Exchange, Series C-1 convertible preferred stock is considered the economic equivalent of Series C common stock and is subject to certain transfer restrictions. Discovery considers the Exchange of the Series A convertible preferred stock for Series A-1 convertible preferred stock and Series C-1 convertible preferred stock to be a modification to the conversion option of the Series A convertible preferred stock. Previously, conversion of Series A preferred stock required simultaneous conversion into Series A common stock and Series C common stock. The Exchange, however, allows for the independent conversion of the Series C-1 convertible preferred stock into Series C common stock without the conversion of Series A-1 convertible preferred stock. Advance/Newhouse’s aggregate voting, economic and preferred rights before the Exchange are equal to its aggregate voting, economic and preferred rights after the Exchange. Discovery valued the securities immediately prior to and immediately after the Exchange and determined that the Exchange increased the fair value of Advance/Newhouse’s preferred stock by $35 million from $3.340 billion to $3.375 billion , or 1.05% , which was not considered significant in the context of the total value of the Company's preferred stock. On the basis of the qualitative and quantitative factors noted above, Discovery does not believe the Exchange is considered significant and does not reflect an extinguishment of the previously issued preferred stock for accounting purposes. Accordingly, Discovery has accounted for the exchange of the previously issued preferred stock as a modification, which is measured as the increase in fair value of the preferred stock held by Advance/Newhouse, or $35 million . In connection with the Exchange Agreement, Advance/Newhouse also entered into the Advance/Newhouse Voting Agreement. The Advance/Newhouse Voting Agreement requires that Advance/Newhouse vote its shares of Discovery Series A-1 convertible preferred stock to approve the issuance of shares of Series C common stock in connection with the Scripps Networks acquisition as contemplated by the Merger Agreement. As the $35 million of incremental value was transferred to Advance/Newhouse in exchange for consent with respect to the Scripps Networks acquisition, the Company determined that the incremental amount should be expensed as acquisition transaction costs, which are reported as a component of selling, general and administrative expense. As of December 31, 2017 , all outstanding shares of Series A-1 and Series C-1 convertible preferred stock are held by Advance/Newhouse. Consistent with the terms of the arrangement prior to the Exchange, holders of Series A-1 and Series C-1 convertible preferred stock have equal rights, powers and privileges, except as otherwise noted. Except for the election of common stock directors, the holders of Series A-1 convertible preferred stock are entitled to vote on matters to which holders of Series A and Series B common stock are entitled to vote, and holders of Series C-1 convertible preferred stock are entitled to vote on matters to which holders of Series C common stock are entitled to vote pursuant to Delaware law. Series A-1 convertible preferred stockholders vote on an as converted to common stock basis together with the Series A and Series B common stockholders as a single class on all matters except the election of directors. Additionally, through its ownership of the Series A-1 convertible preferred stock, Advance/Newhouse has special voting rights on certain matters and the right to elect three directors. Holders of the Company’s common stock are not entitled to vote in the election of such directors. Advance/Newhouse retains these rights so long as it or its permitted transferees own or have the right to vote such shares that equal at least 80% of the shares of Series A-1 convertible preferred stock issued to Advance/Newhouse in connection with the formation of Discovery plus any Series A-1 convertible preferred stock released from escrow, as may be adjusted for certain capital transactions. Subject to the prior preferences and other rights of any senior stock, holders of Series A-1 and Series C-1 convertible preferred stock will participate equally with common stockholders on an as converted to common stock basis in any cash dividends declared by the Board of Directors. In the event of a liquidation, dissolution or winding up of Discovery, after payment of Discovery’s debts and liabilities and subject to the prior payment with respect to any stock ranking senior to Series A-1 and Series C-1 convertible preferred stock, the holders of Series A-1 and Series C-1 convertible preferred stock will receive, before any payment or distribution is made to the holders of any common stock or other junior stock, an amount (in cash or property) equal to $0.01 per share. Following payment of such amount and the payment in full of all amounts owing to the holders of securities ranking senior to Discovery’s common stock, holders of Series A-1 and Series C-1 convertible preferred stock will share equally on an as converted to common stock basis with the holders of common stock with respect to any assets remaining for distribution to such holders. Preferred Stock Conversion and Repurchase s Series C convertible preferred stock held by Advance/Newhouse was, and the Series C-1 preferred stock held by Advance/Newhouse is, convertible, at the option of the holder, into shares of Series C common stock. Prior to the Exchange, the Company had an agreement with Advance/Newhouse to repurchase, on a quarterly basis, a number of shares of Series C convertible preferred stock convertible into Series C common stock based on the number of shares of Series C common stock purchased under the Company’s stock repurchase program during the then most recently completed fiscal quarter. The price paid per share is calculated as 99% of the average price paid for the Series C common shares repurchased by the Company during the applicable fiscal quarter multiplied by the Series C conversion rate. The Advance/Newhouse repurchases are made outside of the Company’s publicly announced common stock repurchase program. The repurchase transactions are recorded as a decrease in par value of preferred stock and retained earnings upon settlement as there is no remaining APIC for this class of stock and the shares are retired upon repurchase. The Advance/Newhouse repurchase agreement was amended on August 7, 2017 to conform the terms of the previous agreement, as detailed above, to the conversion ratio of the newly issued Series C-1 convertible preferred stock. The preferred stock repurchase made during the third quarter of 2017 occurred after the Exchange and, as such, was a repurchase of the newly issued Series C-1 convertible preferred stock. The total price paid for the repurchase of $102 million was the planned amount subject to repurchase under the previous repurchase agreement with Advance/Newhouse, as determined and disclosed in the previous quarter. The number of shares repurchased reflect the post-exchange repurchase of Series C-1 convertible preferred stock and therefore differs from the previously disclosed planned repurchase of Series C convertible preferred shares. There were no additional repurchases of Series C-1 convertible preferred stock during the fourth quarter of 2017. The table below presents a summary of Series C and Series C-1 convertible preferred stock repurchases made under the repurchase agreement (in millions). Year Ended December 31, 2017 2016 Series C Convertible Preferred Stock: Shares repurchased 2.3 9.1 Purchase price $ 120 $ 479 Series C-1 Convertible Preferred Stock: Shares repurchased 0.2 — Purchase price $ 102 $ — There are no planned repurchases of Series C-1 convertible preferred stock for the first quarter of 2018 as there were no repurchases of Series A or Series C common stock during the fourth quarter of 2017. Stock Repurchases As of December 31, 2017 , total shares repurchased, on a split-adjusted and as-converted basis, under these programs were 33% of the Company's common outstanding shares on a fully-diluted basis since the repurchase programs were authorized, including offsetting adjustments for the issuance of equity for share-based compensation. Total shares repurchased excluding the impact of stock compensation, on a split-adjusted and as-converted basis, under these programs represent 38% of the Company's outstanding shares from the time the repurchase programs were authorized. Common Stock Repurchase Contract On March 15, 2017 , the Company settled a December 15, 2016 common stock repurchase contract through the receipt of $58 million of cash. The Company had prepaid $57 million for the common stock repurchase contract in 2016 with the option to settle the contract in cash or Series C common stock in March 2017. The Company elected to receive a cash settlement inclusive of a $1 million premium, which is reflected as an adjustment to APIC. On December 2, 2016 , the Company settled an August 22, 2016 common stock repurchase contract with a net notional value of $71 million whose strike price of $25.86 was below the Series C common stock price at expiry. The Company elected to settle the contract through receipt of 2.8 million shares of Series C common stock at the then current market price equal to $75 million . The receipt of shares is reflected as a component of treasury stock and reclassified from additional paid-in capital at the prepaid cost of $71 million . Other Comprehensive Income (Loss) The table below presents the tax effects related to each component of other comprehensive income (loss) and reclassifications made into the consolidated statements of operations (in millions). Year Ended December 31, 2017 Year Ended December 31, 2016 Year Ended December 31, 2015 Pretax Tax Benefit (Expense) Net-of-tax Pretax Tax Benefit (Expense) Net-of-tax Pretax Tax Benefit (Expense) Net-of-tax Currency translation adjustments: Unrealized gains (losses) Foreign currency $ 280 $ 3 $ 283 $ (234 ) $ 41 $ (193 ) $ (249 ) $ 19 $ (230 ) Net investment hedges (112 ) — (112 ) 3 (1 ) 2 — — — Reclassifications: Loss (gain) on disposition 12 — 12 — — — 23 — 23 Other (expense) income, net — — — — — — 6 — 6 Total currency translation adjustments 180 3 183 (231 ) 40 (191 ) (220 ) 19 (201 ) AFS adjustments: Unrealized gains (losses) 36 (6 ) 30 (34 ) 6 (28 ) (33 ) 6 (27 ) Reclassifications to other (expense) income, net: Other-than-temporary-impairment AFS securities — — — 62 (10 ) 52 — — — Hedged portion of AFS securities (18 ) 3 (15 ) 17 (3 ) 14 2 — 2 Total AFS adjustments 18 (3 ) 15 45 (7 ) 38 (31 ) 6 (25 ) Derivative adjustments: Unrealized (losses) gains (41 ) 15 (26 ) 39 (14 ) 25 23 (8 ) 15 Reclassifications: Distribution revenue 22 (8 ) 14 25 (7 ) 18 (23 ) 8 (15 ) Advertising revenue 3 (1 ) 2 2 — 2 (2 ) — (2 ) Costs of revenues — — — (27 ) 7 (20 ) (9 ) 3 (6 ) Interest expense 1 — 1 3 (1 ) 2 3 (1 ) 2 Other (expense) income, net (17 ) 6 (11 ) (4 ) 1 (3 ) 7 (2 ) 5 Total derivative adjustments (32 ) 12 (20 ) 38 (14 ) 24 (1 ) — (1 ) Other comprehensive income (loss) $ 166 $ 12 $ 178 $ (148 ) $ 19 $ (129 ) $ (252 ) $ 25 $ (227 ) Accumulated Other Comprehensive Loss The table below presents the changes in the components of accumulated other comprehensive loss, net of taxes (in millions). Currency Translation Adjustments AFS Derivative Adjustments Accumulated Other Comprehensive Loss December 31, 2014 $ (367 ) $ (2 ) $ 1 $ (368 ) Other comprehensive (loss) income before reclassifications (230 ) (27 ) 15 (242 ) Reclassifications from accumulated other comprehensive loss to net income 29 2 (16 ) 15 Other comprehensive loss (201 ) (25 ) (1 ) (227 ) Purchase of redeemable noncontrolling interest (61 ) — — (61 ) Other comprehensive loss attributable to redeemable noncontrolling interests 23 — — 23 December 31, 2015 (606 ) (27 ) — (633 ) Other comprehensive (loss) income before reclassifications (191 ) (28 ) 25 (194 ) Reclassifications from accumulated other comprehensive loss to net income — 66 (1 ) 65 Other comprehensive (loss) income (191 ) 38 24 (129 ) December 31, 2016 (797 ) 11 24 (762 ) Other comprehensive income (loss) before reclassifications 171 30 (26 ) 175 Reclassifications from accumulated other comprehensive loss to net loss 12 (15 ) 6 3 Other comprehensive income (loss) 183 15 (20 ) 178 Other comprehensive income attributable to redeemable noncontrolling interests (1 ) — — (1 ) December 31, 2017 $ (615 ) $ 26 $ 4 $ (585 )

Equity-Based Compensation

Equity-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity-Based Compensation	SHARE-BASED COMPENSATION The Company has various incentive plans under which stock options, RSUs, PRSUs and SARs have been issued. As of December 31, 2017 , the Company has reserved a total of 117 million shares of its Series A and Series C common stock for future exercises of outstanding and future grants of stock options and stock-settled SARs and future vesting of outstanding and future grants of PRSUs and RSUs. Upon exercise of stock options and stock-settled SARs or vesting of PRSUs and RSUs, the Company issues new shares from its existing authorized but unissued shares. There were 97 million shares of common stock in reserves that were available for future grant under the incentive plans as of December 31, 2017 . Shared-Based Compensation Expense The table below presents the components of share-based compensation expense (in millions). Year Ended December 31, 2017 2016 2015 RSUs $ 23 $ 17 $ 17 Stock options 12 13 17 PRSUs 6 34 16 SARs (3 ) 4 (14 ) ESPP 1 1 1 Unit awards — — (2 ) Total share-based compensation expense $ 39 $ 69 $ 35 Tax benefit recognized $ 9 $ 25 $ 13 Compensation expense for all awards was recorded in selling, general and administrative expense on the consolidated statements of operations. Liability-classified equity-based compensation awards include certain SARS and PRSUs. The Company recorded total liabilities for cash-settled and other liability-classified equity-based compensation awards of $47 million and $83 million as of December 31, 2017 and 2016 , respectively. The current portion of the liability for cash-settled awards was $12 million and $31 million as of December 31, 2017 and 2016 , respectively. Share-Based Award Activity RSUs The table below presents RSU activity (in millions, except years and weighted-average grant price). RSUs Weighted-Average Grant Price Weighted-Average Remaining Contractual Term (years) Aggregate Fair Value Outstanding as of December 31, 2016 2.6 $ 30.03 Granted 1.6 $ 28.81 Converted (0.4 ) $ 35.91 $ 12 Forfeited (0.4 ) $ 29.61 Outstanding as of December 31, 2017 3.4 $ 28.78 2.6 $ 77 Vested and expected to vest as of December 31, 2017 3.4 $ 28.78 2.6 $ 77 RSUs represent the contingent right to receive shares of the Company's Series A and C common stock, substantially all of which vest ratably each year over periods of one to four years based on continuous service. As of December 31, 2017 , there was $61 million of unrecognized compensation cost related to RSUs, which is expected to be recognized over a weighted-average period of 2.7 years . Stock Options The table below presents stock option activity (in millions, except years and weighted-average exercise price). Stock Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding as of December 31, 2016 13.7 $ 26.05 Granted 2.6 $ 28.74 Exercised (2.5 ) $ 17.54 $ 26 Forfeited (1.5 ) $ 33.46 Outstanding as of December 31, 2017 12.3 $ 27.46 3.5 14 Vested and expected to vest as of December 31, 2017 12.3 $ 27.46 3.5 14 Exercisable as of December 31, 2017 6.7 $ 26.26 2.1 14 Stock options are granted with an exercise price equal to or in excess of the closing market price of the Company’s Series A or Series C common stock on the date of grant. Substantially all stock options vest ratably over three to four years from the grant date based on continuous service and expire seven to ten years from the date of grant. Stock option awards generally provide for accelerated vesting upon retirement or after reaching a specified age and years of service. The Company received cash payments from the exercise of stock options totaling $42 million , $46 million and $16 million during 2017 , 2016 and 2015 , respectively. As of December 31, 2017 , there was $32 million of unrecognized compensation cost, net of actual forfeitures, related to stock options, which is expected to be recognized over a weighted-average period of 2.0 years . The fair value of stock options is estimated using the Black-Scholes option-pricing model. The weighted-average assumptions used to determine the fair value of stock options as of the date of grant during 2017 , 2016 and 2015 were as follows. Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.87 % 1.26 % 1.54 % Expected term (years) 5.0 5.0 5.0 Expected volatility 27.52 % 28.74 % 26.78 % Dividend yield — — — The weighted-average grant date fair value of options granted during 2017 , 2016 and 2015 was $7.99 , $7.09 and $8.44 , respectively, per option. The total intrinsic value of options exercised during 2017 , 2016 and 2015 was $26 million , $42 million and $28 million , respectively. PRSUs The table below presents PRSU activity (in millions, except years and weighted-average grant price). PRSUs Weighted-Average Grant Price Weighted-Average Remaining Contractual Term (years) Aggregate Fair Value Outstanding as of December 31, 2016 4.5 $ 34.44 Granted 0.7 $ 29.50 Converted (1.7 ) $ 34.62 $ 49 Forfeited — $ — Outstanding as of December 31, 2017 3.5 $ 33.41 0.9 76 Vested and expected to vest as of December 31, 2017 3.5 $ 33.41 0.9 76 Convertible as of December 31, 2017 1.5 $ 40.42 — 33 The Company has granted PRSUs to certain senior level executives. PRSUs represent the contingent right to receive shares of the Company’s Series A and C common stock, substantially all of which vest over three to four years based on continuous service and whether the Company achieves certain operating performance targets. The performance targets for substantially all PRSUs are cumulative measures of the Company’s adjusted operating income before depreciation and amortization (as defined in Note 21), free cash flows and revenues over a three year period. The number of PRSUs that vest principally range from 0% to 100% based on a sliding scale where achieving or exceeding the performance target will result in 100% of the PRSUs vesting and achieving less than 80% of the target will result in no portion of the PRSUs vesting. Additionally, for certain PRSUs the Company’s Compensation Committee has discretion in determining the final amount of units that vest, but may not increase the amount of any PRSU award above 100% . Upon vesting, each PRSU becomes convertible into one share of the Company’s Series A or Series C common stock as applicable. Holders of PRSUs do not receive payments of dividends in the event the Company pays a cash dividend until such PRSUs are converted into shares of the Company’s common stock. The Company records compensation expense for PRSUs ratably over the graded vesting service period once it is probable that the performance targets will be achieved. In any period in which the Company determines that achievement of the performance targets is not probable, the Company ceases recording compensation expense and all previously recognized compensation expense for the award is reversed. Compensation expense is separately recorded for each vesting tranche of PRSUs for a particular grant. For certain PRSUs, the Company measures the fair value and related compensation cost based on the closing price of the Company’s Series A or C common stock on the grant date. For PRSUs for which the Company’s Compensation Committee has discretion in determining the final amount of units that vest or in situations where the executive is able to withhold taxes in excess of the minimum statutory requirement, compensation cost is remeasured at each reporting date based on the closing price of the Company’s Series A or Series C common stock. As of December 31, 2017 , unrecognized compensation cost, net of forfeitures, related to PRSUs was $21 million , which is expected to be recognized over a weighted-average period of 1.6 years based on the Company’s current assessment of the PRSUs that will vest, which may differ from actual results. SARs The table below presents SAR award activity (in millions, except years and weighted-average grant price). SARs Weighted- Average Grant Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding as of December 31, 2016 8.6 $ 35.29 Granted 3.0 $ 27.39 Settled (0.6 ) $ 25.72 $ 1 Forfeited (3.3 ) $ 38.60 Outstanding as of December 31, 2017 7.7 $ 31.58 1.0 $ — Vested and expected to vest as of December 31, 2017 7.7 $ 31.58 1.0 $ — SAR award grants include cash-settled SARs and stock-settled SARs. Cash-settled SARs entitle the holder to receive a cash payment for the amount by which the price of the Company’s Series A or Series C common stock exceeds the base price established on the grant date. Cash-settled SARs are granted with a base price equal to or greater than the closing market price of the Company’s Series A or Series C common stock on the date of grant. Stock-settled SARs entitle the holder to shares of Series A or Series C common stock in accordance with the award agreement terms. The fair value of outstanding SARs is estimated using the Black-Scholes option-pricing model. The weighted-average assumptions used to determine the fair value of outstanding SARs were as follows. Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.74 % 0.95 % 0.83 % Expected term (years) 1.0 0.9 0.9 Expected volatility 31.37 % 29.46 % 31.59 % Dividend yield — — — As of December 31, 2017 and 2016 , the weighted-average fair value of SARs outstanding was $1.01 and $1.79 per award. The Company made cash payments of $1 million , $5 million and $11 million to settle exercised SARs during 2017 , 2016 and 2015 , respectively. As of December 31, 2017 , there was $4 million of unrecognized compensation cost, net of actual forfeitures, related to SARs, which is expected to be recognized over a weighted-average period of 0.9 years . Employee Stock Purchase Plan The ESPP enables eligible employees to purchase shares of the Company’s common stock through payroll deductions or other permitted means. Unless otherwise determined by the Company’s Compensation Committee, the purchase price for shares offered under the ESPP is 85% of the closing price of the Company’s Series A common stock on the purchase date. The Company recognizes the fair value of the discount associated with shares purchased in selling, general and administrative expense on the consolidated statement of operations. The Company’s Board of Directors has authorized 9 million shares of the Company’s common stock to be issued under the ESPP. During the years ended December 31, 2017 , 2016 and 2015 the Company issued 179 thousand , 191 thousand and 208 thousand shares under the ESPP, respectively, and received cash totaling $4 million , $4 million and $5 million , respectively. Unit Awards Unit awards represented the contingent right to receive a cash payment for the amount by which the vesting price exceeded the grant price. Because unit awards were cash-settled, the Company remeasured the fair value and compensation expense of outstanding unit awards each reporting date until settlement. During the year ended December 31, 2015, the Company made cash payments of $14 million to settle all 1.2 million remaining unit awards, which had a weighted-average grant price of $20.59 .

Retirement Savings Plans

Retirement Savings Plans	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Retirement Savings Plans	RETIREMENT SAVINGS PLANS The Company has defined contribution and other savings plans for the benefit of its employees that meet eligibility requirements. Eligible employees may contribute a portion of their compensation to the plans, which may be subject to certain statutory limitations. For these plans, the Company also makes contributions including discretionary contributions, subject to plan provisions, which vest immediately. The Company made total contributions of $30 million , $29 million and $36 million during 2017 , 2016 and 2015 , respectively. The Company's contributions were recorded in selling, general and administrative expense in the consolidated statements of operations. The Company’s savings plans include a deferred compensation plan through which members of the Company’s executive team in the U.S. may elect to defer up to 50% of their eligible compensation. The amounts deferred are invested in various mutual funds at the direction of the executive, which are used to finance payment of the deferred compensation obligation. Distributions from the deferred compensation plan are made upon termination or other events as specified in the plan. The Company has established a separate trust to hold the investments that finance the deferred compensation obligation. The accounts of the separate trust are included in the Company’s consolidated financial statements. The investments are included in prepaid expenses and other current assets and the deferred compensation obligation is included in accrued liabilities in the consolidated balance sheets. The values of the investments and deferred compensation obligation are recorded at fair value. Changes in the fair value of the investments are offset by changes in the fair value of the deferred compensation obligation. (See Note 5.)

Restructuring And Other Charges

Restructuring And Other Charges	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring And Other Charges	RESTRUCTURING AND OTHER CHARGES Restructuring and other charges, by reportable segment were as follows (in millions). Year Ended December 31, 2017 2016 2015 U.S. Networks $ 18 $ 15 $ 33 International Networks 42 26 14 Education and Other 3 3 2 Corporate 12 14 1 Total restructuring and other charges $ 75 $ 58 $ 50 Year Ended December 31, 2017 2016 2015 Restructuring charges $ 68 $ 55 $ 29 Other charges 7 3 21 Total restructuring and other charges $ 75 $ 58 $ 50 Restructuring charges include management changes and cost reduction efforts, including employee terminations, intended to enable the Company to more efficiently operate in a leaner and more directed cost structure and invest in growth initiatives, including digital services and content creation. Other charges during 2015 result from content impairments primarily at the Company's U.S. Networks segment due to the cancellation of certain series as a result of legal circumstances pertaining to the associated talent. (See Note 6.) Changes in restructuring and other liabilities by major category were as follows (in millions). Contract Terminations Employee Relocations/ Terminations Total December 31, 2014 $ 4 $ 15 $ 19 Net accruals 3 26 29 Cash paid (5 ) (20 ) (25 ) December 31, 2015 2 21 23 Net accruals 3 52 55 Cash paid (2 ) (37 ) (39 ) December 31, 2016 3 36 39 Net accruals 3 65 68 Cash paid (5 ) (59 ) (64 ) December 31, 2017 $ 1 $ 42 $ 43

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES The domestic and foreign components of income before income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Domestic $ 815 $ 1,414 $ 1,281 Foreign (952 ) 257 278 Income before income taxes $ (137 ) $ 1,671 $ 1,559 The components of the provision for income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Current: Federal $ 177 $ 384 $ 306 State and local 45 (56 ) 57 Foreign 153 152 146 375 480 509 Deferred: Federal (124 ) 45 59 State and local (7 ) — (10 ) Foreign (68 ) (72 ) (47 ) (199 ) (27 ) 2 Income taxes $ 176 $ 453 $ 511 On December 22, 2017, new federal tax reform legislation was enacted in the United States, resulting in significant changes from previous tax law. The TCJA revised the U.S. corporate income tax by among other things, lowering the statutory corporate tax rate from 35% to 21% and reinstating bonus depreciation that will allow for full expensing of qualified property, for property placed in service before 2023, including qualified film. The TCJA also eliminated or significantly amended certain deductions (interest, domestic production activities deduction and executive compensation). The TCJA fundamentally changed taxation of multinational entities by moving from a system of worldwide taxation with deferral to a hybrid territorial system, featuring a participation exemption regime with current taxation of certain foreign income. Included in the international provisions was the enactment of a minimum tax on low-taxed foreign earnings, and new measures to deter base erosion and promote U.S. production. In addition, the TCJA imposed a mandatory repatriation toll tax on unremitted foreign earnings. Notwithstanding the U.S. taxation of these amounts, we intend to continue to invest most or all of these earnings, as well as our capital in these subsidiaries, indefinitely outside of the U.S. and do not expect to incur any significant, additional taxes related to such amounts. To the extent that a company’s accounting for certain income tax effects of the TCJA is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate in the financial statements and the TCJA provides a measurement period that should not extend beyond one year from the TCJA enactment date. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply the tax laws that were in effect immediately before the enactment of the TCJA. Although not effective until January 1, 2018, the Company has calculated its best estimate of the TCJA impact in its year end income tax provision and as a result has recorded $44 million as an income tax benefit. Our federal income tax expense for periods beginning in 2018 will be based on the new rate. The mandatory repatriation toll charge resulted in a tax expense which was mostly offset by available foreign tax credits. We have recorded provisional amounts for several of the impacts of the new tax law including: the deemed repatriation tax on post-1986 accumulated earnings and profits, the deferred tax rate change effect of the new law, gross foreign tax credit carryforwards and related valuation allowances to offset foreign tax credit carryforwards. Certain items or estimates that result in impacts of the TCJA being provisional include: detailed foreign earnings calculations for the most recent period, projected foreign cash balances for certain foreign subsidiaries and finalized computations of foreign tax credit availability. In addition, our 2017 US federal income tax return will not be finalized until later in 2018, and while historically this process has resulted in offsetting changes in estimates in current and deferred taxes for items which are timing related, the reduction of the US tax rate will result in adjustments to our income tax provision when recorded. Finally, we consider it likely that further technical guidance regarding certain of the new provisions included in the TCJA, as well as clarity regarding state income tax conformity to current federal tax code, may be issued. We have reported provisional amounts for the income tax effects of the TCJA for which the accounting is incomplete but a reasonable estimate could be determined. Based on a continued analysis of the estimates and further guidance and interpretations on the application of the law, additional revisions may occur throughout the allowable measurement period. The following table reconciles the Company's effective income tax rate to the U.S. federal statutory income tax rate of 35% . Year Ended December 31, 2017 2016 2015 U.S. federal statutory income tax rate 35 % 35 % 35 % State and local income taxes, net of federal tax benefit (18 )% (2 )% 2 % Effect of foreign operations 25 % (1 )% 1 % Domestic production activity deductions 39 % (4 )% (3 )% Change in uncertain tax positions (44 )% — % (1 )% Preferred stock modification (9 )% — % — % Goodwill impairment (334 )% — % — % Renewable energy investments tax credits 142 % (1 )% — % Impact of Tax Reform Act 32 % — % — % Other, net 4 % — % (1 )% Effective income tax rate (128 )% 27 % 33 % Income tax expense was $176 million and $453 million and our effective tax rate was (128)% and 27% for 2017 and 2016 , respectively. During 2017, the decrease in the effective tax rate was primarily attributable to the impact of a goodwill impairment charge that is non-deductible for tax purposes. Thereafter, the decrease in the effective tax rate was primarily due to investment tax credits that we receive related to our renewable energy investments, and to a lesser extent, the domestic production activity deduction benefit, the allocation and taxation of income among multiple foreign and domestic jurisdictions, and the impact of the TCJA. The benefits were partially offset by an increase in reserves for uncertain tax positions in 2017. In 2016, we favorably resolved multi-year state tax positions that resulted in a reduction of reserves related to uncertain tax positions that did not recur in 2017. Components of deferred income tax assets and liabilities were as follows (in millions). December 31, 2017 2016 Deferred income tax assets: Accounts receivable $ 5 $ 2 Tax attribute carry-forward 151 67 Accrued liabilities and other 190 174 Total deferred income tax assets 346 243 Valuation allowance (105 ) (25 ) Net deferred income tax assets 241 218 Deferred income tax liabilities: Intangible assets (315 ) (384 ) Content rights (82 ) (166 ) Equity method investments (68 ) (76 ) Notes receivable (3 ) (7 ) Other (28 ) (32 ) Total deferred income tax liabilities (496 ) (665 ) Net deferred income tax liabilities $ (255 ) $ (447 ) The Company’s net deferred income tax assets and liabilities were reported on the consolidated balance sheets as follows (in millions). December 31, 2017 2016 Noncurrent deferred income tax assets (included within other noncurrent assets) $ 64 $ 20 Deferred income tax liabilities (classified on the balance sheet) (319 ) (467 ) Net deferred income tax liabilities $ (255 ) $ (447 ) The Company’s loss carry-forwards were reported on the consolidated balance sheets as follows (in millions). State Foreign Loss carry-forwards $ 176 $ 1,109 Deferred tax asset related to loss carry-forwards 12 61 Valuation allowance against loss carry-forwards (11 ) (17 ) Earliest expiration date of loss carry-forwards 2018 2018 A reconciliation of the beginning and ending amounts of unrecognized tax benefits (without related interest and penalty amounts) is as follows (in millions). Year Ended December 31, 2017 2016 2015 Beginning balance $ 117 $ 173 $ 176 Additions based on tax positions related to the current year 27 13 30 Additions for tax positions of prior years 57 19 17 Additions for tax positions acquired in business combinations — — 3 Reductions for tax positions of prior years — (60 ) (21 ) Settlements (8 ) (16 ) (16 ) Reductions due to lapse of statutes of limitations (6 ) (9 ) (13 ) Changes due to foreign currency exchange rates 2 (3 ) (3 ) Ending balance $ 189 $ 117 $ 173 The balances as of December 31, 2017 , 2016 and 2015 included $189 million , $117 million and $173 million , respectively, of unrecognized tax benefits that, if recognized, would reduce the Company’s income tax expense and effective tax rate after giving effect to interest deductions and offsetting benefits from other tax jurisdictions. For the year ended December 31, 2017 , increases in unrecognized tax benefits related to the uncertainty of allocation and taxation of income among multiple jurisdictions was offset by the movements of tax positions as a result of multiple audit resolutions and lapse of statutes of limitations. The Company and its subsidiaries file income tax returns in the U.S. and various state and foreign jurisdictions. The Internal Revenue Service recently completed audit procedures for its 2008 to 2011 tax years, the results of which should be finalized in the coming year. The Company is currently under audit by the Internal Revenue Service for its 2012 to 2014 consolidated federal income tax returns. It is difficult to predict the final outcome or timing of resolution of any particular tax matter. Accordingly, an estimate of any related impact to the reserve for uncertain tax positions cannot currently be determined. With few exceptions, the Company is no longer subject to audit by any jurisdiction for years prior to 2006. Adjustments that arose from the completion of audits for certain tax years have been included in the change in uncertain tax positions in the table above. It is reasonably possible that the total amount of unrecognized tax benefits related to certain of the Company's uncertain tax positions could decrease by as much as $53 million within the next twelve months as a result of ongoing audits, lapses of statutes of limitations or regulatory developments. As of December 31, 2017 , 2016 and 2015 , the Company had accrued approximately $21 million , $11 million and $20 million , respectively, of total interest and penalties payable related to unrecognized tax benefits. The Company recognizes interest and penalties related to unrecognized tax benefits as a component of income tax expense.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE In calculating earnings per share, the Company follows the two-class method, which distinguishes between the classes of securities based on the proportionate participation rights of each security type in the Company's undistributed (loss) income. The Company's Series A, B and C common stock and the Series C-1 convertible preferred stock are treated as one class for purposes of applying the two-class method, because they have substantially equal rights and share equally on an as converted basis with respect to (loss) income available to Discovery Communications, Inc. Pursuant to the Exchange Agreement with Advance/Newhouse, Discovery issued newly designated shares of Series A-1 and Series C-1 preferred stock in exchange for all outstanding shares of Discovery's Series A and Series C convertible participating preferred stock (see Note 12). The Exchange is treated as a reverse stock split and the Company has recast historical basic and diluted earnings per share available to Series C-1 preferred stockholders (previously Series C preferred stockholders). Prior to the Exchange Agreement, Series C convertible preferred stock was convertible into Series C common stock at a conversion rate of 2.0 shares of Series C common stock for each shares of Series C convertible preferred stock. Following the Exchange, the Series C-1 preferred stock may be converted into Series C common stock at a conversion rate of 19.3648 shares of Series C common stock for each share of Series C-1 preferred stock. As such, the Company has retrospectively restated basic and diluted earnings per share information for Discovery's Series C-1 preferred stock for the years ended December 31, 2016 and December 31, 2015 . The Exchange did not impact historical basic and diluted earnings per share attributable to the Company's Series A, B and C common stockholders. The table below sets forth the computation for (loss) income available to Discovery Communications, Inc. stockholders (in millions). Year Ended December 31, 2017 2016 2015 Numerator: Net (loss) income $ (313 ) $ 1,218 $ 1,048 Less: Allocation of undistributed income to Series A-1 convertible preferred stock 41 (139 ) (113 ) Net income attributable to noncontrolling interests — (1 ) (1 ) Net income attributable to redeemable noncontrolling interests (24 ) (23 ) (13 ) Net (loss) income available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders for basic net income per share $ (296 ) $ 1,055 $ 921 Allocation of net (loss) income available to Discovery Communications Inc. Series A, B and C common stockholders and Series C-1 convertible preferred stockholders for basic net (loss) income per share: Series A, B and C common stockholders (225 ) 789 686 Series C-1 convertible preferred stockholders (71 ) 266 235 Total (296 ) 1,055 921 Add: Allocation of undistributed income to Series A-1 convertible preferred stockholders (41 ) 139 113 Net (loss) income available to Discovery Communications, Inc. Series A, B and C common stockholders for diluted net (loss) income per share $ (337 ) $ 1,194 $ 1,034 Net (loss) income available to Discovery Communications, Inc. Series C-1 convertible preferred stockholders for diluted net (loss) income per share is included in net (loss) income available to Discovery Communications, Inc. Series A, B and C common stockholders for diluted net (loss) income per share. For the year ended December 31, 2017 net loss available to Discovery Communications, Inc. Series C-1 convertible preferred stockholders for diluted loss per share was $71 million . For the years ended December 31, 2016 and December 31, 2015 net income available to Discovery Communications, Inc. Series C-1 convertible preferred stockholders for diluted earnings per share was $265 million and $234 million , respectively. The table below sets forth the weighted average number of shares outstanding utilized in determining the denominator for basic and diluted (loss) earnings per share (in millions). Year Ended December 31, 2017 2016 2015 Denominator - weighted average: Series A, B and C common shares outstanding — basic 384 401 432 Impact of assumed preferred stock conversion 192 206 219 Dilutive effect of share-based awards — 3 5 Series A, B and C common shares outstanding — diluted 576 610 656 Series C-1 convertible preferred stock outstanding — basic and diluted 6 7 8 The weighted average number of diluted shares outstanding adjusts the weighted average number of shares of Series A, B and C common stock outstanding for the potential dilution that would occur if common stock equivalents, including convertible preferred stock and share-based awards, were converted into common stock or exercised, calculated using the treasury stock method. Series A, B and C diluted common stock includes the impact of the conversion of Series A-1 preferred stock, the impact of the conversion of Series C-1 preferred stock, and the impact of share-based compensation to the extent it is not anti-dilutive. For 2017 , the weighted average number of shares outstanding for the computation of diluted loss per share does not include 2 million of share-based awards, as the effects of these potentially outstanding shares would have been anti-dilutive. Prior to the Exchange, Series C convertible preferred stock was convertible into Series C common stock at a conversion rate of 2.0 shares of Series C common stock for each share of Series C convertible preferred stock. Following the exchange, the Series C-1 preferred stock may be converted into Series C common stock at a conversion rate of 19.3648 shares of Series C common stock for each shares of Series C-1 preferred stock. The table below sets forth the Company's calculated (loss) earnings per share. Year Ended December 31, 2017 2016 2015 Basic net (loss) income per share available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders: Series A, B and C common stockholders $ (0.59 ) $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ (11.33 ) $ 38.07 $ 30.74 Diluted net (loss) income per share available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders: Series A, B and C common stockholders $ (0.59 ) $ 1.96 $ 1.58 Series C-1 convertible preferred stockholders $ (11.33 ) $ 37.88 $ 30.54 (Loss) earnings per share amounts may not recalculate due to rounding. The computation of the diluted (loss) earnings per share of Series A, B and C common stockholders assumes the conversion of Series A-1 and C-1 convertible preferred stock, while the diluted earnings per share amounts of Series C-1 convertible preferred stock does not assume conversion of those shares. The table below presents the details of the anticipated stock repurchases and share-based awards and that were excluded from the calculation of diluted (loss) earnings per share (in millions). Year Ended December 31, 2017 2016 2015 Anti-dilutive share-based awards 19 8 6 PRSUs whose performance targets have not yet been achieved 2 4 3 Anti-dilutive common stock repurchase contracts — 2 — Only outstanding PRSUs whose performance targets have been achieved as of the last day of the most recent period are included in the dilutive effect calculation.

Supplemental Disclosures

Supplemental Disclosures	12 Months Ended
	Dec. 31, 2017
Disclosure Text Block Supplement [Abstract]
Supplemental Disclosures	SUPPLEMENTAL DISCLOSURES Valuation and Qualifying Accounts Changes in valuation and qualifying accounts consisted of the following (in millions). Beginning of Year Additions Write-offs Utilization End of Year 2017 Allowance for doubtful accounts $ 47 $ 12 $ (4 ) $ — $ 55 Deferred tax valuation allowance 25 84 (4 ) — 105 2016 Allowance for doubtful accounts 40 13 (6 ) — 47 Deferred tax valuation allowance 19 9 (3 ) — 25 2015 Allowance for doubtful accounts 39 8 (7 ) — 40 Deferred tax valuation allowance 13 6 — — 19 Accrued Liabilities Accrued liabilities consisted of the following (in millions). December 31, 2017 2016 Accrued payroll and related benefits $ 535 $ 486 Content rights payable 219 173 Accrued interest 148 67 Accrued income taxes 45 34 Current portion of share-based compensation liabilities 12 31 Other accrued liabilities 350 284 Total accrued liabilities $ 1,309 $ 1,075 Other (Expense) Income, net Other (expense) income, net , consisted of the following (in millions). Year Ended December 31, 2017 2016 2015 Foreign currency (losses) gains, net $ (83 ) $ 75 $ (103 ) (Losses) gains on derivative instruments, net (82 ) (12 ) 5 Remeasurement gain on previously held equity interest 33 — 2 Interest income (a) 21 — — Other-than-temporary impairment of AFS investments — (62 ) — Other 1 3 (1 ) Total other (expense) income, net $ (110 ) $ 4 $ (97 ) (a) Interest income for 2017 is comprised of interest on proceeds from issuance of senior notes to fund the anticipated Scripps Networks acquisition. Of the $6.8 billion in senior notes issued, $2.7 billion were invested in money market funds, $1.3 billion were invested in time deposit accounts, and the remainder was invested in highly liquid, short-term instruments with original maturities of 90 days or less. (See Note 4 and Note 9.) Share-Based Plan Payments, net Share-based plan payments, net in the statement of cash flows consisted of the following (in millions). (a) Year Ended December 31, 2017 2016 2015 Tax settlements associated with share-based plans $ (30 ) $ (11 ) $ (27 ) Proceeds from issuance of common stock in connection with share-based plans 46 50 21 Total share-based plan payments, net $ 16 $ 39 $ (6 ) (a) Share-based plan payments, net includes the retrospective reclassification of windfall tax benefits or deficiencies from financing activities to operating activities in the statement of cash flows presentation pursuant to the adoption of the new guidance on share-based payments on January 1, 2017 . There were $7 million and $12 million in net windfall tax adjustments for the years ended December 31, 2016 and December 31, 2015 , respectively, reclassified from financing activities to operating activities. (See Note 2.) Supplemental Cash Flow Information Year Ended December 31, 2017 2016 2015 Cash paid for taxes, net (a) $ 274 $ 527 $ 653 Cash paid for interest 357 343 312 Noncash investing and financing activities: Contributions of business and assets of strategic ventures Fair value of assets and liabilities of business received in exchange for redeemable noncontrolling interests (b) 144 — — Fair value of investment received, net of cash paid — 82 — Net asset value of contributed business — 32 — Contingent consideration obligations from business acquisitions — — 13 Accrued purchases of property and equipment 24 42 12 Contingent consideration receivable from business dispositions — — 6 Assets acquired under capital lease arrangements 103 37 5 (a) The decrease in cash paid for taxes, net, is mostly due to the tax benefits from the Company's investments in limited liability companies that sponsor renewable energy projects. (See Note 4.) (b) Amount relates to the Company's VTEN joint venture. (See Note 3.) The joint venture was affected via DCL's contribution of the Velocity network to a newly formed entity, VTEN, which is a non-guarantor subsidiary of the Company and is reflected as a non-cash contribution in the condensed consolidating financial statements. (See Note 23.) The table above does not include the November 30, 2017 acquisition of a controlling interest in OWN from Harpo. The Company increased its ownership stake from 49.50% to 73.99% . The table above does not include the March 31, 2015 acquisition of an additional 31% interest in Eurosport France. The Company increased its ownership stake from 20% to 51% . Upon consolidation a cash payment for a portion of these businesses resulted in inclusion of the fair value of all of the net assets and liabilities of OWN and Eurosport France in Discovery's consolidated financial statements. (See Note 3.)

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS In the normal course of business, the Company enters into transactions with related parties. Related parties include entities that share common directorship, such as Liberty Global plc (“Liberty Global”), Liberty Broadband Corporation ("Liberty Broadband") and their subsidiaries and equity method investees (together the “Liberty Group”). Discovery’s Board of Directors includes Mr. Malone, who is Chairman of the Board of Liberty Global and beneficially owns approximately 26% of the aggregate voting power with respect to the election of directors of Liberty Global. Mr. Malone is also Chairman of the Board of Liberty Broadband and beneficially owns approximately 46% of the aggregate voting power with respect to the election of directors of Liberty Broadband. The majority of the revenue earned from the Liberty Group relates to multi-year network distribution arrangements. Related party transactions also include revenues and expenses for content and services provided to or acquired from equity method investees, such as All3Media and a Russian cable television business, or minority partners of consolidated subsidiaries, such as Hasbro. For the year ended December 31, 2017 , related party transaction costs include expenses associated with the Exchange Agreement executed with Advance/Newhouse. The table below presents a summary of the transactions with related parties, including OWN prior to the November 30, 2017 acquisition (in millions). Year Ended December 31, 2017 2016 2015 Revenues and service charges: Liberty Group (a) $ 476 $ 387 $ 171 Equity method investees (b) 145 129 62 Other 46 32 35 Total revenues and service charges $ 667 $ 548 $ 268 Interest income (c) $ 13 $ 17 $ 23 Expenses $ (178 ) $ (102 ) $ (67 ) (a) The increase for the year ended December 31, 2017 reflects the May 2016 acquisition of Time Warner Cable, Inc. by Charter Communications, an equity method investee of the Liberty Group and other changes in the Liberty Group's businesses. (b) The increases to revenue from equity method investees for the years ended December 31, 2017 and 2016 relate to the joint venture agreement with the New Russian Business which began in October 2015. (See Note 3.) (c) The Company records interest earnings from loans to equity method investees as a component of income from equity method investees, net, in the consolidated statements of operations. (See Note 4.) The table below presents receivables due from related parties (in millions). December 31, 2017 2016 Receivables $ 105 $ 109 Note receivable (a) — 311 (a) The decrease for the year ended December 31, 2017 reflects the November 2017 acquisition of OWN by Discovery (See Note 3.) The receivable is recorded as a component of Discovery's consolidated financial statements.

Commitments And Contingencies

Commitments And Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	COMMITMENTS AND CONTINGENCIES Contractual Commitments As of December 31, 2017 , the Company’s significant contractual commitments, including related payments due by period, were as follows (in millions). Leases Year Ending December 31, Operating Capital Content Other Total 2018 $ 61 $ 48 $ 1,075 $ 332 $ 1,516 2019 52 36 558 241 887 2020 36 33 750 175 994 2021 28 30 342 54 454 2022 17 23 350 29 419 Thereafter 36 95 771 89 991 Total minimum payments 230 265 3,846 920 5,261 Amounts representing interest — (40 ) — — (40 ) Total $ 230 $ 225 $ 3,846 $ 920 $ 5,221 The Company enters into multi-year lease arrangements for transponders, office space, studio facilities, and other equipment. Leases are not cancelable prior to their expiration. On January 9, 2018, we issued a press release announcing a new real estate strategy with plans to relocate the Company's global headquarters from Silver Spring, Maryland to New York City in 2019. As of December 31, 2017, we did not meet the held for sale classification criteria, as defined in GAAP as it is uncertain that the sale of the Silver Spring property will be completed within the next twelve months. Content purchase commitments are associated with third-party producers and sports associations for content that airs on the television networks. Production contracts generally require the purchase of a specified number of episodes with payments over the term of the license. Production contracts include both programs that have been delivered and are available for airing and programs that have not yet been produced or sporting events that have not yet taken place. If the content is ultimately never produced, the Company's commitments expire without obligation. The commitments disclosed above exclude content liabilities recognized on the consolidated balance sheet. Other purchase obligations include agreements with certain vendors and suppliers for the purchase of goods and services whereby the underlying agreements are enforceable, legally binding and specify all significant terms. Significant purchase obligations include transmission services, television rating services, marketing research, employment contracts, equipment purchases, and information technology services. Some of these contracts do not require the purchase of fixed or minimum quantities and generally may be terminated with a 30-day to 60-day advance notice without penalty, and are not included in the table above past the 30-day to 60-day advance notice period. Amounts related to employment contracts include base compensation, but do not include compensation contingent on future events. Although the Company had funding commitments to equity method investees as of December 31, 2017 , the Company may also provide uncommitted additional funding to its equity method investments in the future. (See Note 4.) Contingencies Put Rights The Company has granted put rights related to certain consolidated subsidiaries. Harpo, Golden Tree, Hasbro and J:COM have the right to require the Company to purchase their remaining noncontrolling interests in OWN, VTEN, Discovery Family and Discovery Japan, respectively. The Company recorded the value of the put rights for OWN, VTEN, Discovery Family and Discovery Japan as a component of redeemable noncontrolling interests in the amounts of $55 million , $120 million , $210 million and $27 million , respectively. (See Note 11.) Legal Matters The Company is party to various lawsuits and claims in the ordinary course of business. However, a determination as to the amount of the accrual required for such contingencies is highly subjective and requires judgments about future events. Although the outcome of these matters cannot be predicted with certainty and the impact of the final resolution of these matters on the Company's results of operations in a particular subsequent reporting period is not known, management does not believe that the resolution of these matters will have a material adverse effect on our consolidated financial position, future results of operations or liquidity. On September 20, 2017 , a putative class action lawsuit captioned Inzlicht-Sprei v. Scripps Networks Interactive, et al. (Case No. 3:17-cv-00420), which we refer to as the “Inzlicht-Sprei action”, was filed in the United States District Court for the Eastern District of Tennessee. A putative class action lawsuit captioned Berg v. Scripps Networks Interactive, et al. (Case No. 2:17-cv-848), which we refer to as the “Berg action”, and a lawsuit captioned Wagner v. Scripps Networks Interactive, et al. (Case No. 2:17-cv-859), which we refer to as the “Wagner action”, were filed in the United States District Court for the Southern District of Ohio on September 27, 2017 and September 29, 2017 , respectively. We refer to the Inzlicht-Sprei action, Berg action and Wagner action collectively as the “actions”. The actions alleged that the defendants filed a materially incomplete and misleading Form S-4 in violation of Sections 14(a) and 20(a) of the Exchange Act and SEC Rule 14a-9. On October 12, 2017 , the plaintiff in the Inzlicht-Sprei action filed a notice of voluntary dismissal without prejudice. On November 21, 2017 , the plaintiffs in both the Berg action and the Wagner action filed notices of voluntary dismissal. Guarantees There were no guarantees recorded as of December 31, 2017 and December 31, 2016 . The Company may provide or receive indemnities intended to allocate business transaction risks. Similarly, the Company may remain contingently liable for certain obligations of a divested business in the event that a third party does not fulfill its obligations under an indemnification obligation. The Company records a liability for its indemnification obligations and other contingent liabilities when probable and estimable. There were no material amounts for indemnifications or other contingencies recorded as of December 31, 2017 and 2016 .

Reportable Segments

Reportable Segments	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Reportable Segments	REPORTABLE SEGMENTS The Company’s operating segments are determined based on (i) financial information reviewed by its chief operating decision maker ("CODM"), the Chief Executive Officer ("CEO"), (ii) internal management and related reporting structure, and (iii) the basis upon which the CEO makes resource allocation decisions. The accounting policies of the reportable segments are the same as the Company’s, except that certain inter-segment transactions that are eliminated for consolidation are not eliminated at the segment level. Inter-segment transactions primarily include the purchase of advertising and content between segments. The Company evaluates the operating performance of its segments based on financial measures such as revenues and adjusted operating income before depreciation and amortization (“Adjusted OIBDA”). Adjusted OIBDA is defined as operating income excluding: (i) mark-to-market share-based compensation, (ii) depreciation and amortization, (iii) restructuring and other charges, (iv) certain impairment charges, (v) gains and losses on business and asset dispositions, and (vi) certain inter-segment eliminations related to production studios. In addition, beginning with the quarter ended September 30, 2017, Adjusted OIBDA also excludes incremental third party transaction costs directly related to the Scripps Networks acquisition and planned integration. The Company uses this measure to assess the operating results and performance of its segments, perform analytical comparisons, identify strategies to improve performance and allocate resources to each segment. The Company believes Adjusted OIBDA is relevant to investors because it allows them to analyze the operating performance of each segment using the same metric management uses. The Company excludes mark-to-market share-based compensation, restructuring and other charges, certain impairment charges, gains and losses on business and asset dispositions and Scripps Networks transaction and integration costs from the calculation of Adjusted OIBDA due to their impact on comparability between periods. The Company also excludes depreciation of fixed assets and amortization of intangible assets, as these amounts do not represent cash payments in the current reporting period. Certain corporate expenses are excluded from segment results to enable executive management to evaluate segment performance based upon the decisions of segment executives. As of January 1, 2017, the Company no longer excludes amortization of deferred launch incentives in calculating total Adjusted OIBDA as it is not material. For the years ended December 31, 2017, 2016 and 2015, deferred launch incentives of $3 million , $13 million and $16 million , respectively, were not reflected as an adjustment to the calculation of total Adjusted OIBDA in order to conform to the current presentation. Total Adjusted OIBDA should be considered in addition to, but not a substitute for, operating income, net (loss) income and other measures of financial performance reported in accordance with GAAP. The tables below present summarized financial information for each of the Company’s reportable segments, other operating segments and corporate and inter-segment eliminations (in millions). Revenues Year Ended December 31, 2017 2016 2015 U.S. Networks $ 3,434 $ 3,285 $ 3,131 International Networks 3,281 3,040 3,092 Education and Other 158 174 173 Corporate and inter-segment eliminations — (2 ) (2 ) Total revenues $ 6,873 $ 6,497 $ 6,394 Adjusted OIBDA Year Ended December 31, 2017 2016 2015 U.S. Networks $ 2,026 $ 1,922 $ 1,774 International Networks 859 835 945 Education and Other 6 (10 ) (2 ) Corporate and inter-segment eliminations (360 ) (334 ) (335 ) Total Adjusted OIBDA $ 2,531 $ 2,413 $ 2,382 Reconciliation of Net (Loss) Income available to Discovery Communications, Inc. to total Adjusted OIBDA Year Ended December 31, 2017 2016 2015 Net (loss) income available to Discovery Communications, Inc. $ (337 ) $ 1,194 $ 1,034 Net income attributable to redeemable noncontrolling interests 24 23 13 Net income attributable to noncontrolling interests — 1 1 Income tax expense 176 453 511 (Loss) income before income taxes (137 ) 1,671 1,559 Other expense (income), net 110 (4 ) 97 Loss (income) from equity investees, net 211 38 (1 ) Loss on extinguishment of debt 54 — — Interest expense 475 353 330 Operating income 713 2,058 1,985 Loss (gain) on disposition 4 (63 ) 17 Restructuring and other charges 75 58 50 Depreciation and amortization 330 322 330 Impairment of goodwill 1,327 — — Mark-to-market equity-based compensation 3 38 — Scripps Networks transaction and integration costs 79 — — Total Adjusted OIBDA $ 2,531 $ 2,413 $ 2,382 Total Assets December 31, 2017 2016 U.S. Networks $ 4,127 $ 3,412 International Networks 5,187 4,922 Education and Other 394 399 Corporate and inter-segment eliminations 12,847 6,939 Total assets $ 22,555 $ 15,672 Total assets for corporate and inter-segment eliminations include goodwill that is allocated to the Company's segments to account for goodwill. The presentation of segment assets in the table above is consistent with the financial reports that are reviewed by the Company's CEO. The goodwill allocated from corporate assets to U.S. Networks and International Networks to account for goodwill is included in the goodwill balances disclosed in Note 8. Content Amortization and Impairment Expense Year Ended December 31, 2017 2016 2015 U.S. Networks $ 776 $ 756 $ 771 International Networks 1,126 1,008 931 Education and Other 8 9 7 Total content amortization and impairment expense $ 1,910 $ 1,773 $ 1,709 Content amortization and impairment expenses are generally included in costs of revenues on the consolidated statements of operations (see Note 6). Revenues by Geography Year Ended December 31, 2017 2016 2015 U.S. $ 3,560 $ 3,411 $ 3,261 Non-U.S. 3,313 3,086 3,133 Total revenues $ 6,873 $ 6,497 $ 6,394 Distribution and advertising revenues are attributed to each country based on viewer location. Other revenues are attributed to each country based on customer location. Property and Equipment by Geography December 31, 2017 2016 U.S. $ 309 $ 258 U.K. 173 107 Other 115 117 Total property and equipment, net $ 597 $ 482 Property and equipment balances are allocated to each country based on the location of the asset.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Selected Quarterly Financial Information [Abstract]
Selected Quarterly Financial Data (Unaudited)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) 2017 (a, b, c,) 1st quarter 2nd quarter 3rd quarter 4th quarter Revenues $ 1,613 $ 1,745 $ 1,651 $ 1,864 Operating income (loss) 487 630 433 (837 ) Net income (loss) 221 380 223 (1,137 ) Net income (loss) available to Discovery Communications, Inc. 215 374 218 (1,144 ) Earnings per share available to Discovery Communications, Inc. Series A, B and C common stockholders Basic $ 0.37 $ 0.65 $ 0.38 $ (1.99 ) Diluted (e) $ 0.37 $ 0.64 $ 0.38 $ (1.99 ) 2016 (d) 1st quarter 2nd quarter 3rd quarter 4th quarter Revenues $ 1,561 $ 1,708 $ 1,556 $ 1,672 Operating income 489 586 458 525 Net income 269 415 225 309 Net income available to Discovery Communications, Inc. 263 408 219 304 Earnings per share available to Discovery Communications, Inc. Series A, B and C common stockholders Basic $ 0.42 $ 0.66 $ 0.37 $ 0.52 Diluted $ 0.42 $ 0.66 $ 0.36 $ 0.52 (a) Goodwill impairment expense of $1.3 billion was recognized during the fourth quarter of 2017. (See Note 8.) (b) On September 25, 2017 , the Company acquired a 67.5% controlling interest in VTEN, a new joint venture with GoldenTree, in exchange for its contribution of the Velocity network. On November 30, 2017 , the Company acquired a controlling interest in OWN from Harpo, increasing Discovery’s ownership stake from 49.50% to 73.99% . Discovery paid $70 million in cash and recognized a gain of $33 million to account for the difference between the carrying value and the fair value of the previously held 49.50% equity interest. On April 28, 2017 , the Company sold Raw and Betty to All3Media and recorded a loss of $4 million upon disposition. (See Note 3.) As of December 31, 2017 , the Company has incurred transaction and integration costs for the Scripps Networks acquisition of $79 million , including the $35 million charge associated with the modification of Advance/Newhouse's preferred stock. (See Note 12.) (c ) In March 2017, DCL completed a cash tender offer for $600 million aggregate principal amount of DCL's 5.05% senior notes due 2020 and 5.625% senior notes due 2019 . This transaction resulted in a pretax loss on extinguishment of debt of $54 million for the year ended December 31, 2017 , which is presented as a separate line item on the Company's consolidated statements of operations and recognized as a component of financing cash outflows on the consolidated statements of cash flows. The loss included $50 million for premiums to par value, $2 million of non-cash write-offs of unamortized deferred financing costs, $1 million for the write-off of the original issue discount of these senior notes and $1 million accrued for other third-party fees. (See Note 10.) (d) On September 30, 2016, the Company recorded an other-than-temporary impairment of $62 million related to its investment in Lionsgate. On December 2, 2016, the Company acquired a 39% minority interest in Group Nine Media, a newly formed media holding company, in exchange for contributions of $100 million and the Company's digital businesses Seeker and SourceFed, resulting in a gain of $50 million upon deconsolidation of the businesses. (See Note 3.) (e) Amounts may not sum to annual total due to rounding.

Condensed Consolidating Financi

Condensed Consolidating Financial Statements	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Consolidating Financial Statements	CONDENSED CONSOLIDATING FINANCIAL INFORMATION Overview As of December 31, 2017 and 2016 , all of the outstanding senior notes have been issued by DCL, a wholly-owned subsidiary of Discovery Communications Holding LLC (“DCH”), which is a wholly-owned subsidiary of the Company, pursuant to one or more Registration Statements on Form S-3 filed with the U.S. Securities and Exchange Commission ("SEC"). (See Note 9.) The Company fully and unconditionally guarantees the senior notes on an unsecured basis. Each of the Company, DCH, and/or DCL (collectively the “Issuers”) may issue additional debt securities under the Company's current Registration Statement on Form S-3 that are fully and unconditionally guaranteed by the other Issuers. Set forth below are condensed consolidating financial statements presenting the financial position, results of operations and comprehensive income and cash flows of (i) the Company, (ii) DCH, (iii) DCL, (iv) the non-guarantor subsidiaries of DCL on a combined basis, (v) the other non-guarantor subsidiaries of the Company on a combined basis, and (vi) reclassifications and eliminations necessary to arrive at the consolidated financial statement balances for the Company. DCL and the non-guarantor subsidiaries of DCL are the primary operating subsidiaries of the Company. DCL primarily includes the Discovery Channel and TLC networks in the U.S. The non-guarantor subsidiaries of DCL include substantially all of the Company’s other U.S. and international networks, education businesses, and most of the Company’s websites and digital distribution arrangements. The non-guarantor subsidiaries of DCL are wholly-owned subsidiaries of DCL with the exception of certain equity method investments. DCL is a wholly-owned subsidiary of DCH. The Company wholly owns DCH through a 33 1/3% direct ownership interest and a 66 2/3% indirect ownership interest through Discovery Holding Company (“DHC”), a wholly-owned subsidiary of the Company. DHC is included in the other non-guarantor subsidiaries of the Company. On September 25, 2017 , the Company acquired a 67.5% controlling interest in VTEN, a new joint venture with GoldenTree, in exchange for its contribution of the Velocity network. The VTEN non-cash transaction and all related financial activity is included within the non-guarantor subsidiaries of DCL. (See Note 3.) The Company's 2016 minority investment in Group Nine Media and all related financial activity is included within the DCL issuer entity in the accompanying condensed consolidated financial statements. (See Note 4.) Basis of Presentation Solely for purposes of presenting the condensed consolidating financial statements, investments in the Company’s subsidiaries have been accounted for by their respective parent company using the equity method. Accordingly, in the following condensed consolidating financial statements the equity method has been applied to (i) the Company’s interests in DCH and the other non-guarantor subsidiaries of the Company, (ii) DCH’s interest in DCL, and (iii) DCL’s interests in the non-guarantor subsidiaries of DCL. Inter-company accounts and transactions have been eliminated to arrive at the consolidated financial statement amounts for the Company. The Company’s accounting bases in all subsidiaries, including goodwill and recognized intangible assets, have been pushed down to the applicable subsidiaries. The operations of certain of the Company’s international subsidiaries are excluded from the Company’s consolidated U.S. income tax return. Tax expense related to permanent differences has been allocated to the entity that created the difference. Tax expense related to temporary differences has been allocated to the entity that created the difference, where identifiable. The remaining temporary differences are allocated to each entity included in the Company’s consolidated U.S. income tax return based on each entity’s relative pretax income. Deferred taxes have been allocated based upon the temporary differences between the carrying amounts of the respective assets and liabilities of the applicable entities. The condensed consolidating financial statements should be read in conjunction with the consolidated financial statements of the Company. CONDENSED CONSOLIDATING BALANCE SHEET December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and ASSETS Current assets: Cash and cash equivalents $ — $ — $ 6,800 $ 509 $ — $ — $ 7,309 Receivables, net — — 410 1,428 — — 1,838 Content rights, net — — 4 406 — — 410 Prepaid expenses and other current assets 49 32 204 149 — — 434 Inter-company trade receivables, net — — 205 — — (205 ) — Total current assets 49 32 7,623 2,492 — (205 ) 9,991 Investment in and advances to subsidiaries 4,563 4,532 6,951 — 3,056 (19,102 ) — Noncurrent content rights, net — — 672 1,541 — — 2,213 Goodwill, net — — 3,677 3,396 — — 7,073 Intangible assets, net — — 259 1,511 — — 1,770 Equity method investments — — 25 310 — — 335 Other noncurrent assets, including property and equipment, net — 20 364 809 — (20 ) 1,173 Total assets $ 4,612 $ 4,584 $ 19,571 $ 10,059 $ 3,056 $ (19,327 ) $ 22,555 LIABILITIES AND EQUITY Current liabilities: Current portion of debt $ — $ — $ 7 $ 23 $ — $ — $ 30 Other current liabilities — — 572 1,269 — — 1,841 Inter-company trade payables, net — — — 205 — (205 ) — Total current liabilities — — 579 1,497 — (205 ) 1,871 Noncurrent portion of debt — — 14,163 592 — — 14,755 Other noncurrent liabilities 2 — 297 606 21 (20 ) 906 Total liabilities 2 — 15,039 2,695 21 (225 ) 17,532 Redeemable noncontrolling interests — — — 413 — — 413 Total equity 4,610 4,584 4,532 6,951 3,035 (19,102 ) 4,610 Total liabilities and equity $ 4,612 $ 4,584 $ 19,571 $ 10,059 $ 3,056 $ (19,327 ) $ 22,555 CONDENSED CONSOLIDATING BALANCE SHEET December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and ASSETS Current assets: Cash and cash equivalents $ — $ — $ 20 $ 280 $ — $ — $ 300 Receivables, net — — 421 1,074 — — 1,495 Content rights, net — — 8 302 — — 310 Prepaid expenses and other current assets 62 36 180 119 — — 397 Inter-company trade receivables, net — — 195 — — (195 ) — Total current assets 62 36 824 1,775 — (195 ) 2,502 Investment in and advances to subsidiaries 5,106 5,070 7,450 — 3,417 (21,043 ) — Noncurrent content rights, net — — 663 1,426 — — 2,089 Goodwill, net — — 3,769 4,271 — — 8,040 Intangible assets, net — — 272 1,240 — — 1,512 Equity method investments, including note receivable — — 30 527 — — 557 Other noncurrent assets, including property and equipment, net — 20 306 666 — (20 ) 972 Total assets $ 5,168 $ 5,126 $ 13,314 $ 9,905 $ 3,417 $ (21,258 ) $ 15,672 LIABILITIES AND EQUITY Current liabilities: Current portion of debt $ — $ — $ 52 $ 30 $ — $ — $ 82 Other current liabilities — — 516 963 — — 1,479 Inter-company trade payables, net — — — 195 — (195 ) — Total current liabilities — — 568 1,188 — (195 ) 1,561 Noncurrent portion of debt — — 7,315 526 — — 7,841 Other noncurrent liabilities 1 — 361 498 20 (20 ) 860 Total liabilities 1 — 8,244 2,212 20 (215 ) 10,262 Redeemable noncontrolling interests — — — 243 — — 243 Total equity 5,167 5,126 5,070 7,450 3,397 (21,043 ) 5,167 Total liabilities and equity $ 5,168 $ 5,126 $ 13,314 $ 9,905 $ 3,417 $ (21,258 ) $ 15,672 CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,988 $ 4,897 $ — $ (12 ) $ 6,873 Costs of revenues, excluding depreciation and amortization — — 467 2,191 — (2 ) 2,656 Selling, general and administrative 53 — 309 1,416 — (10 ) 1,768 Impairment of goodwill — — — 1,327 — — 1,327 Depreciation and amortization — — 42 288 — — 330 Restructuring and other charges — — 35 40 — — 75 Loss on disposition — — — 4 — — 4 Total costs and expenses 53 — 853 5,266 — (12 ) 6,160 Operating (loss) income (53 ) — 1,135 (369 ) — — 713 Equity in loss of subsidiaries (288 ) (288 ) (541 ) — (192 ) 1,309 — Interest expense — — (448 ) (27 ) — — (475 ) Loss on extinguishment of debt — — (54 ) — — — — (54 ) Loss from equity investees, net — — (3 ) (208 ) — — (211 ) Other (expense) income, net — — (204 ) 94 — — (110 ) Loss before income taxes (341 ) (288 ) (115 ) (510 ) (192 ) 1,309 (137 ) Income tax benefit (expense) 4 — (173 ) (7 ) — — (176 ) Net loss (337 ) (288 ) (288 ) (517 ) (192 ) 1,309 (313 ) Net income attributable to redeemable noncontrolling interests — — — — — (24 ) (24 ) Net loss available to Discovery Communications, Inc. $ (337 ) $ (288 ) $ (288 ) $ (517 ) $ (192 ) $ 1,285 $ (337 ) CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,963 $ 4,547 $ — $ (13 ) $ 6,497 Costs of revenues, excluding depreciation and amortization — — 466 1,970 — (4 ) 2,432 Selling, general and administrative 14 — 292 1,393 — (9 ) 1,690 Depreciation and amortization — — 41 281 — — 322 Restructuring and other charges — — 28 30 — — 58 Gain on disposition — — (50 ) (13 ) — — (63 ) Total costs and expenses 14 — 777 3,661 — (13 ) 4,439 Operating (loss) income (14 ) — 1,186 886 — — 2,058 Equity in earnings of subsidiaries 1,203 1,203 602 — 802 (3,810 ) — Interest expense — — (332 ) (21 ) — — (353 ) Loss from equity investees, net — — (3 ) (35 ) — — (38 ) Other income (expense), net — — 40 (36 ) — — 4 Income before income taxes 1,189 1,203 1,493 794 802 (3,810 ) 1,671 Income tax benefit (expense) 5 — (290 ) (168 ) — — (453 ) Net income 1,194 1,203 1,203 626 802 (3,810 ) 1,218 Net income attributable to noncontrolling interests — — — — — (1 ) (1 ) Net income attributable to redeemable noncontrolling interests — — — — — (23 ) (23 ) Net income available to Discovery Communications, Inc. $ 1,194 $ 1,203 $ 1,203 $ 626 $ 802 $ (3,834 ) $ 1,194 CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,909 $ 4,498 $ — $ (13 ) $ 6,394 Costs of revenues, excluding depreciation and amortization — — 500 1,847 — (4 ) 2,343 Selling, general and administrative 15 — 265 1,398 — (9 ) 1,669 Depreciation and amortization — — 35 295 — — 330 Restructuring and other charges — — 28 22 — — 50 Loss on disposition — — — 17 — — 17 Total costs and expenses 15 — 828 3,579 — (13 ) 4,409 Operating (loss) income (15 ) — 1,081 919 — — 1,985 Equity in earnings of subsidiaries 1,044 1,044 505 — 696 (3,289 ) — Interest expense — — (318 ) (12 ) — — (330 ) Income (loss) from equity investees, net — — 4 (3 ) — — 1 Other income (expense), net — — 9 (106 ) — — (97 ) Income before income taxes 1,029 1,044 1,281 798 696 (3,289 ) 1,559 Income tax benefit (expense) 5 — (237 ) (279 ) — — (511 ) Net income 1,034 1,044 1,044 519 696 (3,289 ) 1,048 Net income attributable to noncontrolling interests — — — — — (1 ) (1 ) Net loss attributable to redeemable noncontrolling interests — — — — — (13 ) (13 ) Net income available to Discovery Communications, Inc. $ 1,034 $ 1,044 $ 1,044 $ 519 $ 696 $ (3,303 ) $ 1,034 CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE (LOSS) INCOME For the Year Ended to December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net loss $ (337 ) $ (288 ) $ (288 ) $ (517 ) $ (192 ) $ 1,309 $ (313 ) Other comprehensive (loss) income, net of tax: Currency translation 183 183 183 186 122 (674 ) 183 Available-for-sale securities 15 15 15 15 10 (55 ) 15 Derivatives (20 ) (20 ) (20 ) (9 ) (13 ) 62 (20 ) Comprehensive loss (159 ) (110 ) (110 ) (325 ) (73 ) 642 (135 ) Comprehensive income attributable to redeemable noncontrolling interests (1 ) (1 ) (1 ) (1 ) (1 ) (20 ) (25 ) Comprehensive loss attributable to Discovery Communications, Inc. $ (160 ) $ (111 ) $ (111 ) $ (326 ) $ (74 ) $ 622 $ (160 ) CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME For the Year Ended to December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net income $ 1,194 $ 1,203 $ 1,203 $ 626 $ 802 $ (3,810 ) $ 1,218 Other comprehensive (loss) income, net of tax: Currency translation (191 ) (191 ) (191 ) (190 ) (127 ) 699 (191 ) Available-for-sale securities 38 38 38 38 25 (139 ) 38 Derivatives 24 24 24 22 16 (86 ) 24 Comprehensive income 1,065 1,074 1,074 496 716 (3,336 ) 1,089 Comprehensive income attributable to noncontrolling interests — — — — — (1 ) (1 ) Comprehensive income attributable to redeemable noncontrolling interests (23 ) (23 ) (23 ) (23 ) (15 ) 84 (23 ) Comprehensive income attributable to Discovery Communications, Inc. $ 1,042 $ 1,051 $ 1,051 $ 473 $ 701 $ (3,253 ) $ 1,065 CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME For the Year Ended to December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net income $ 1,034 $ 1,044 $ 1,044 $ 519 $ 696 $ (3,289 ) $ 1,048 Other comprehensive (loss) income, net of tax: Currency translation (201 ) (201 ) (201 ) (199 ) (134 ) 735 (201 ) Available-for-sale securities (25 ) (25 ) (25 ) (25 ) (17 ) 92 (25 ) Derivatives (1 ) (1 ) (1 ) (3 ) (1 ) 6 (1 ) Comprehensive income 807 817 817 292 544 (2,456 ) 821 Comprehensive income attributable to noncontrolling interests — — — — — (1 ) (1 ) Comprehensive loss attributable to redeemable noncontrolling interests 23 23 23 23 15 (97 ) 10 Comprehensive income attributable to Discovery Communications, Inc. $ 830 $ 840 $ 840 $ 315 $ 559 $ (2,554 ) $ 830 CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (3 ) $ 3 $ 476 $ 1,153 $ — $ — $ 1,629 Investing Activities Payments for investments — — (45 ) (399 ) — — (444 ) Purchases of property and equipment — — (43 ) (92 ) — — (135 ) Distributions from equity method investees — — — 77 — — 77 Proceeds from dispositions, net of cash disposed — — — 29 — — 29 Payments for derivative instruments, net — — (111 ) 10 — — (101 ) Business acquisitions, net of cash acquired — — — (60 ) — — (60 ) Inter-company distributions — — 42 — — (42 ) — Other investing activities, net — — (1 ) 2 — — 1 Cash used in investing activities — — (158 ) (433 ) — (42 ) (633 ) Financing Activities Commercial paper repayments, net — — (48 ) — — — (48 ) Borrowings under revolving credit facility — — 350 — — — 350 Principal repayments of revolving credit facility — — (475 ) — — — (475 ) Borrowings from debt, net of discount and including premiums — — 7,488 — — — 7,488 Principal repayments of debt, including discount payment and premiums to par value — — (650 ) — — — (650 ) Payments for bridge financing commitment fees — — (40 ) — — — (40 ) Principal repayments of capital lease obligations — — (7 ) (26 ) — — (33 ) Repurchases of stock (603 ) — — — — — (603 ) Cash settlement of common stock repurchase contracts 58 — — — — — 58 Distributions to redeemable noncontrolling interests — — — (30 ) — — (30 ) Share-based plan proceeds, net 16 — — — — — 16 Inter-company distributions — — — (42 ) — 42 — Inter-company contributions and other financing activities, net 532 (3 ) (156 ) (455 ) — — (82 ) Cash provided by (used in) financing activities 3 (3 ) 6,462 (553 ) — 42 5,951 Effect of exchange rate changes on cash and cash equivalents — — — 62 — — 62 Net change in cash and cash equivalents — — 6,780 229 — — 7,009 Cash and cash equivalents, beginning of period — — 20 280 — — 300 Cash and cash equivalents, end of period $ — $ — $ 6,800 $ 509 $ — $ — $ 7,309 CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (20 ) $ (9 ) $ 249 $ 1,160 $ — $ — $ 1,380 Investing Activities Payments for investments — — (124 ) (148 ) — — (272 ) Purchases of property and equipment — — (18 ) (70 ) — — (88 ) Proceeds from dispositions, net of cash disposed — — — 19 — — 19 Distributions from equity method investees — — — 87 — — 87 Inter-company distributions — — 30 — — (30 ) — Other investing activities, net — — — (2 ) — — (2 ) Cash used in investing activities — — (112 ) (114 ) — (30 ) (256 ) Financing Activities Commercial paper repayments, net — — (45 ) — — — (45 ) Borrowings under revolving credit facility — — 350 263 — — 613 Principal repayments of revolving credit facility — — (225 ) (610 ) — — (835 ) Borrowings from debt, net of discount and including premiums — — 498 — — — 498 Principal repayments of capital lease obligations — — (5 ) (23 ) — — (28 ) Repurchases of stock (1,374 ) — — — — — (1,374 ) Prepayments of common stock repurchase contracts (57 ) — — — — — (57 ) Distributions to redeemable noncontrolling interests — — — (22 ) — — (22 ) Share-based plan proceeds, net 39 — — — — — 39 Hedge of borrowings from debt instruments — — 40 — — — 40 Inter-company distributions — — — (30 ) — 30 — Inter-company contributions and other financing activities, net 1,412 9 (733 ) (701 ) — — (13 ) Cash provided by (used in) financing activities 20 9 (120 ) (1,123 ) — 30 (1,184 ) Effect of exchange rate changes on cash and cash equivalents — — — (30 ) — — (30 ) Net change in cash and cash equivalents — — 17 (107 ) — — (90 ) Cash and cash equivalents, beginning of period — — 3 387 — — 390 Cash and cash equivalents, end of period $ — $ — $ 20 $ 280 $ — $ — $ 300 CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (122 ) $ (15 ) $ 427 $ 1,004 $ — $ — $ 1,294 Investing Activities Payments for investments — — (10 ) (262 ) — — (272 ) Purchases of property and equipment — — (17 ) (86 ) — — (103 ) Distributions from equity method investees — — — 87 — — 87 Proceeds from disposition, net of cash disposed — — — 61 — — 61 Payments for derivative instruments, net — — (11 ) 2 — — (9 ) Business acquisitions, net of cash acquired — — — (80 ) — — (80 ) Inter-company distributions — — 37 — — (37 ) — Other investing activities, net — — — 15 — — 15 Cash used in investing activities — — (1 ) (263 ) — (37 ) (301 ) Financing Activities Commercial paper repayments, net — — (136 ) — — — (136 ) Borrowings under revolving credit facility — — — 1,016 — — 1,016 Principal repayments of revolving credit facility — — (13 ) (252 ) — — (265 ) Borrowings from debt, net of discount and including premiums — — 936 — — — 936 Principal repayments of debt, including discount payment and premiums to par value — — (854 ) — — — (854 ) Principal repayments of capital leases obligations — — (5 ) (22 ) — — (27 ) Repurchases of stock (951 ) — — — — — (951 ) Purchase of redeemable noncontrolling interests — — — (548 ) — — (548 ) Distributions to redeemable noncontrolling interests — — — (42 ) — — (42 ) Share-based plan payments, net (6 ) — — — — — (6 ) Hedge of borrowings from debt distributions — — (29 ) — — — (29 ) Inter-company distributions — — — (37 ) — 37 — Inter-company contributions and other financing activities, net 1,079 15 (330 ) (777 ) — — (13 ) Cash provided by (used in) financing activities 122 15 (431 ) (662 ) — 37 (919 ) Effect of exchange rate changes on cash and cash equivalents — — — (51 ) — — (51 ) Net change in cash and cash equivalents — — (5 ) 28 — — 23 Cash and cash equivalents, beginning of period — — 8 359 — — 367 Cash and cash equivalents, end of period $ — $ — $ 3 $ 387 $ — $ — $ 390

Summary Of Significant Accoun31

Summary Of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Accounting and Reporting Pronouncements Adopted	Accounting and Reporting Pronouncements Adopted Statement of Cash Flows In November 2016, the Financial Accounting Standard Board ("FASB") issued guidance that reduces diversity in practice in how certain cash receipts and cash payments are classified in the statement of cash flows. The topics relevant to the Company include: (1) debt prepayment or debt extinguishment costs, which prior to adoption were classified as operating activities, but are now classified as financing activities, (2) settlement and receipt of discounts and premiums associated with our senior notes, which prior to adoption were classified as operating activities, but are now classified as financing activities when the stated interest rate is deemed not insignificant to the effective interest rate of the borrowing, (3) contingent consideration payments not made soon after a business combination date, which must be classified as financing activities up to the contingent consideration liability amount with any excess payment classified as operating activities, and (4) the election to assess distributions received from equity method investees based on the nature of distribution approach, which results in the classification of such distributions based on the nature of the activity that generated the distribution as either a return on investment (classified as cash inflows from operating activities) or a return of investment (classified as cash inflows from investing activities). The Company early adopted this guidance retrospectively effective January 1, 2017 resulting in a reclassification of $5 million of debt extinguishment costs from operating activities to financing activities in the consolidated statement of cash flows for the year ended December 31, 2015 . There was no impact on other prior periods presented for the first and second items listed above and no change in the Company's historical accounting policy was required for the third and fourth items.
Accounting and Reporting Pronouncements Not Yet Adopted	Share-Based Payments In March 2016 , the FASB issued guidance that simplifies how share-based payments are accounted for and presented in the financial statements. Implementation of the new accounting guidance was effective January 1, 2017 , and impacted the financial statements as follows: • Actual forfeitures will be used in the calculations of share-based compensation expense instead of estimated forfeitures. Retained earnings were decreased by approximately $4 million to affect the modified retrospective method impact of the adoption as of January 1, 2017 . • Net windfall tax benefits or deficiencies are recorded in income tax expense in the period in which they occur, whereas they were previously recorded in additional paid-in capital (“APIC”). This change has been applied prospectively. There were $7 million and $ 12 million in net tax windfall adjustments for the years ended December 31, 2016 and December 31, 2015 , respectively. • Expected cash flows from windfall tax benefits are no longer factored into the calculation of the number of shares for diluted earnings per share. This change has been applied prospectively. Net windfall tax benefits did not impact the presentation of diluted earnings per share for the years ended December 31, 2016 and December 31, 2015 by more than $0.01 per share. • Cash flows from net windfall tax benefits are classified as operating activities in the statement of cash flows presentation. Previously net windfall tax benefits were classified as financing activities. This change was applied on a retrospective basis resulting in adjustments to prior period amounts. As a result, there were $7 million and $12 million in net tax windfall adjustments for the years ended December 31, 2016 and December 31, 2015 , respectively, reclassified from financing activities to operating activities. • The Company evaluated the accounting for awards that are liability-classified and marked-to-market each accounting period and concluded that there is no change to the accounting for those awards. Balance Sheet Classification of Deferred Income Taxes In November 2015, the FASB issued guidance that removes the requirement to separate deferred tax assets and liabilities into current and noncurrent amounts, and instead requires all such amounts be classified as noncurrent on the Company's consolidated balance sheets. As a result, each tax jurisdiction will now have only one net noncurrent deferred tax asset or liability. The new guidance does not change the existing requirement that prohibits offsetting deferred tax liabilities from one jurisdiction against deferred tax assets of another jurisdiction. The Company retrospectively adopted the new guidance effective January 1, 2017. The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 ) Business Combinations In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which were recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The Company adopted this guidance effective January 1, 2016 and has applied it on a prospective basis. Accounting for Fees Paid in a Cloud Computing Arrangement In April 2015, the FASB issued explicit guidance on the recognition of fees paid by a customer for cloud computing arrangements as either the acquisition of a software license or a service contract. The Company adopted this guidance effective October 1, 2015, and there was no effect on the consolidated financial statements. Business Consolidation In February 2015, the FASB issued guidance that amends the analysis that a reporting entity performs to determine whether it should consolidate certain legal entities. The changes in this guidance include how related parties and de facto agents are considered in the primary beneficiary determination and the analysis for determining whether a fee paid to a decision maker or service provider is a variable interest. The Company adopted this guidance effective January 1, 2016, and there was no effect on the consolidated financial statements. Presentation of Financial Statements - Going Concern In August 2014, the FASB issued guidance requiring the Company to perform interim and annual assessments regarding conditions or events that raise substantial doubt about the Company's ability to continue as a going concern for a period of one year after the financial statements are issued, and to provide related disclosures, if applicable. If such conditions or events exist, an entity should disclose that there is substantial doubt about the entity's ability to continue as a going concern for a period of one year after the financial statements are issued , along with the principal conditions or events that raise substantial doubt, management's evaluation of the significance of those conditions or events in relation to the entity's ability to meet its obligations, and management's plans that are intended to mitigate those conditions or events. The Company adopted this guidance for the year ended December 31, 2016 , and concluded that as of December 31, 2017 there were no conditions or events that raise substantial doubt about the Company's ability to continue as a going concern for one year after the financial statements are issued. Accounting and Reporting Pronouncements Not Yet Adopted Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income In February 2018, the FASB issued updated guidance which permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of the tax reform legislation ("the 2017 Tax Act" or "the Tax Act") to retained earnings for each period in which the effect of the change is recorded. The update also requires entities to disclose their accounting policy for releasing income tax effects from accumulated other comprehensive income. The updated guidance is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements. Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued significant amendments to hedge accounting which expand the eligibility for hedge accounting to more financial and nonfinancial hedging strategies. The guidance is intended to align hedge accounting with companies’ risk management strategies, simplify the application of hedge accounting, and increase transparency as to the scope and results of hedging programs. In addition, the guidance amends the presentation and disclosure requirements and changes how companies assess effectiveness. The updated guidance is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements. Goodwill Under the current accounting guidance, the quantitative goodwill impairment test is performed using a two-step process. The first step of the process is to compare the fair value of a reporting unit with its carrying amount, including goodwill. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not impaired and the second step of the quantitative impairment test is not necessary. If the carrying amount of a reporting unit exceeds its fair value, the second step of the quantitative goodwill impairment test is required to be performed to measure the amount of impairment loss, if any. The second step of the quantitative goodwill impairment test compares the implied fair value of the reporting unit’s goodwill with the carrying amount of that goodwill. The implied fair value of goodwill is determined in the same manner as the amount of goodwill recognized in a business combination. In other words, the estimated fair value of the reporting unit’s identifiable net assets excluding goodwill is compared to the fair value of the reporting unit as if the reporting unit had been acquired in a business combination and the fair value of the reporting unit was the purchase price paid. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss, such as the $1.3 billion recorded for the year ended December 31, 2017 in the consolidated statements of operations, is recognized in an amount equal to that excess (see Note 8). In January 2017, the FASB issued guidance that simplifies the subsequent measurement of goodwill. The new guidance eliminates Step 2 from the goodwill impairment test, and eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment. Therefore, an entity will recognize impairment charges for the amount by which the carrying amount exceeds the reporting unit's fair value, and the same impairment assessment applies to all reporting units. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017 . The amendments in this update must be adopted on a prospective basis for the annual or any interim goodwill impairment tests beginning after December 15, 2019 . If the Company had early adopted this accounting pronouncement, the impact of the current period goodwill impairment would have been approximately $100 million , substantially less than the impairment charge recorded under the current guidance. Accounting changes and error corrections In January 2017, the FASB issued guidance which states that registrants should consider additional qualitative disclosures if the impact of an issued but not yet adopted ASU is unknown or cannot be reasonably estimated and to include a description of the effect of the accounting policies that the registrant expects to apply, if determined. This guidance is effective immediately. Transition guidance in certain issued but not yet adopted standards has been updated to reflect this amendment. Clarifying the definition of a business In January 2017, the FASB issued guidance that amends the definition of a business and provides a threshold which must be considered to determine whether a transaction is an acquisition (or disposal) of an asset or a business. Under the current accounting guidance, the minimum inputs and processes required for a “set” of assets and activities to meet the definition of a business is not specified. That lack of clarity has led to broad interpretations of the definition of a business. Under this guidance, when substantially all of the fair value of gross assets acquired is concentrated in a single asset (or group of similar assets), the assets acquired would not represent a business. In addition, in order to be considered a business, an acquisition would have to include at a minimum an input and a substantive process that together significantly contribute to the ability to create an output. The amended guidance also narrows the definition of outputs by more closely aligning it with how outputs are described in FASB guidance for revenue recognition. The guidance is effective on a prospective basis beginning January 1, 2018 and is not expected to have a material impact on the Company’s consolidated financial statements. Income Taxes In October 2016, the FASB issued guidance that simplifies the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. The new guidance includes requirements to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs, and therefore eliminates the exception for an intra-entity transfer of an asset other than inventory. The new standard is effective January 1, 2018. The Company is currently analyzing the impact of the pronouncement to the consolidated financial statements. Leases In February 2016 , the FASB issued guidance on leases that will require lessees to recognize almost all of their leases on the balance sheet by recording a right-of-use asset and liability. The new standard will be effective for reporting periods beginning after December 15, 2018 , and the new accounting guidance may be applied at the beginning of the earliest comparative period presented in the year of adoption or at effective date without applying the provisions of the new guidance to comparative periods presented. The Company is currently evaluating the impact that the pronouncement will have on the consolidated financial statements; however, it is expected that assets and liabilities will increase materially when operating leases are recorded under the new standard. The method of transition will be determined when the Company has completed its evaluation. Recognition and Measurement of Financial Instruments In January 2016 , the FASB issued guidance regarding the classification and measurement of financial instruments, which among other changes in accounting and disclosure requirements, replaces the cost method of accounting for non-marketable equity securities with a model for recognizing impairments and observable price changes, and also eliminates the available-for-sale classification for marketable equity securities. The standard requires equity securities, including available-for-sale ("AFS") securities, to be measured at fair value with changes in the fair value recognized through net income, superseding the guidance permitting entities to record gains and losses on equity securities with readily determinable fair values in accumulated other comprehensive income. Investments accounted for under the equity method of accounting or that result in consolidation are not included within the scope of this update. The new standard will affect the Company's accounting for AFS securities for reporting periods beginning after December 15, 2017 . The Company will apply the guidance on a modified retrospective basis. The transition adjustment to reclassify accumulated other comprehensive income to retained earnings is expected to be $26 million . (See Note 12.) Revenue from Contracts with Customers In May 2014 , the FASB issued an accounting pronouncement related to revenue recognition, which applies a single, comprehensive revenue recognition model for all contracts with customers. The core principle of the new guidance is that the Company will recognize revenue from the transfer of promised goods or services to customers at an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those goods or services. Subsequent to the issuance of the May 2014 guidance, several clarifications and updates have been issued by the FASB on this topic, the most recent of which was issued in December 2016. Many of these clarifications and updates to the guidance, as well as a number of interpretive issues, apply to companies in the media and entertainment industry. The guidance requires new or expanded disclosures related to the judgments made by companies when following the framework. The Company is nearing completion of its assessment of the impact of adopting this new guidance, and the Company will implement the new revenue standard beginning January 1, 2018. The Company currently does not anticipate that the adoption of the new guidance will have a material impact on the Company's financial statements, principally because the Company does not expect significant changes in the way it will record distribution or advertising revenues. The Company will apply the guidance on a modified retrospective basis.
Use of Estimates	Use of Estimates The preparation of financial statements in accordance with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates, judgments and assumptions that affect the amounts and disclosures reported in the consolidated financial statements and accompanying notes. Management continually re-evaluates its estimates, judgments and assumptions, and management’s evaluations could change. These estimates are sometimes complex, sensitive to changes in assumptions and require fair value determinations using Level 3 fair value measurements. Actual results may differ materially from those estimates. Estimates and judgments inherent in the preparation of the consolidated financial statements include accounting for asset impairments, revenue recognition, allowances for doubtful accounts, content rights, depreciation and amortization, business combinations, share-based compensation, income taxes, other financial instruments, contingencies, and the determination of whether the Company is the primary beneficiary of entities in which it holds variable interests.
Consolidation	Consolidation The Company has ownership and other interests in various entities, including corporations, partnerships, and limited liability companies. For each such entity, the Company evaluates its ownership and other interests to determine whether it should consolidate the entity or account for its ownership interest as an investment. As part of its evaluation, the Company initially determines whether the entity is a VIE and, if so, whether it is the primary beneficiary of the VIE. An entity is generally a VIE if it meets any of the following criteria: (i) the entity has insufficient equity to finance its activities without additional subordinated financial support from other parties, (ii) the equity investors cannot make significant decisions about the entity’s operations, or (iii) the voting rights of some investors are not proportional to their obligations to absorb the expected losses of the entity or receive the expected returns of the entity and substantially all of the entity’s activities involve or are conducted on behalf of the investor with disproportionately few voting rights. The Company consolidates VIEs for which it is the primary beneficiary, regardless of its ownership or voting interests. The primary beneficiary is the party involved with the VIE that (i) has the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance, and (ii) has the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. Upon inception of a variable interest or the occurrence of a reconsideration event, the Company makes judgments in determining whether entities in which it invests are VIEs. If so, the Company makes judgments to determine whether it is the primary beneficiary and is thus required to consolidate the entity. If it is concluded that an entity is not a VIE, then the Company considers its proportional voting interests in the entity. The Company consolidates majority-owned subsidiaries in which a controlling financial interest is maintained. A controlling financial interest is determined by majority ownership and the absence of substantive third-party participating rights. Ownership interests in entities for which the Company has significant influence that are not consolidated under the Company’s consolidation policy are accounted for as equity method investments. Related party transactions between the Company and its equity method investees have not been eliminated. (See Note 19.)
Investments	Investments The Company holds investments in equity method investees, cost method investees and available-for-sale securities. Investments in equity method investees are those for which the Company has the ability to exercise significant influence, but does not control and is not the primary beneficiary. Significant influence typically exists if the Company has a 20% to 50% ownership interest in the venture unless persuasive evidence to the contrary exists. Under this method of accounting, the Company typically records its proportionate share of the net earnings or losses of equity method investees and a corresponding increase or decrease to the investment balances. Cash payments to equity method investees such as additional investments, loans and advances and expenses incurred on behalf of investees, as well as payments from equity method investees such as dividends, distributions and repayments of loans and advances are recorded as adjustments to investment balances. For the Company's equity method investments in renewable energy limited liability companies where the capital structure of the equity investment results in different liquidation rights and priorities than what is reflected by the underlying percentage ownership interests, the Company's proportionate share of net earnings is accounted for using the Hypothetical Liquidation at Book Value ("HLBV") methodology available under the equity method of accounting. When applying HLBV, the Company determines the amount that would be received if the investment were to liquidate all of its assets and distribute the resulting cash to the investors based on contractually defined liquidation priorities, assuming the entity continues as a going concern. The change in the Company's claim on the investee's book value in accordance with GAAP at the beginning and the end of the reporting period, after adjusting for any contributions or distributions, is the Company's share of the earnings or losses for the period. The Company evaluates its equity method investments for impairment whenever events or changes in circumstances indicate that the carrying amounts of such investments may not be recoverable. (See "Asset Impairment Analysis" below.) Cost method investments include ownership rights that either (i) do not meet the definition of in-substance common stock or (ii) do not provide the Company with control or significant influence and these investments do not have readily determinable fair values. Cost method investments are recorded at the lower of cost or fair value. Investments in entities or other securities in which the Company has no control or significant influence and is not the primary beneficiary and have a readily determinable fair value are accounted for at fair value based on quoted market prices are classified as either trading securities or available-for-sale securities. For investments classified as trading securities, which include securities held in a separate trust in connection with the Company’s deferred compensation plan, unrealized and realized gains and losses related to the investment and corresponding liability are recorded in earnings as a component of other income (expense), net , on the consolidated statements of operations. For investments classified as AFS, which include investments in common stock, unrealized gains and losses are recorded, net of income taxes, in other comprehensive (loss) income until the security is sold or considered impaired. If declines in the value of AFS securities are determined to be other-than-temporary, a loss is recorded in earnings in the current period as a component of other income (expense), net on the consolidated statements of operations. (See "Asset Impairment Analysis" below.) For purposes of computing realized gains and losses, the Company determines cost on a specific identification basis.
Foreign Currency	Foreign Currency The reporting currency of the Company is the U.S. dollar. The functional currency of most of the Company’s international subsidiaries is the local currency. Assets and liabilities, including inter-company balances for which settlement is anticipated in the foreseeable future, denominated in foreign currencies are translated at exchange rates in effect at the balance sheet date. Foreign currency equity balances are translated at historical rates. Revenues and expenses denominated in foreign currencies are translated at average exchange rates for the respective periods. Foreign currency translation adjustments are recorded in accumulated other comprehensive income. Transactions denominated in currencies other than subsidiaries’ functional currencies are recorded based on exchange rates at the time such transactions arise. Changes in exchange rates with respect to amounts recorded in the consolidated balance sheets related to these items will result in unrealized foreign currency transaction gains and losses based upon period-end exchange rates. The Company also records realized foreign currency transaction gains and losses upon settlement of the transactions. Foreign currency transaction gains and losses are included in other (expense) income, net , and totaled a loss of $83 million , a gain of $75 million , and a loss of $103 million for 2017 , 2016 and 2015 , respectively. Cash flows from the Company's operations in foreign countries are generally translated at the weighted average rate for the applicable period in the consolidated statements of cash flows. The impacts of material transactions are recorded at the applicable spot rates as of the transaction date in the consolidated statements of operations and cash flows. The effects of exchange rates on cash balances held in foreign currencies are separately reported in the Company's consolidated statements of cash flows.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid investments with original maturities of 90 days or less.
Accounts Receivable	Receivables Receivables include amounts billed and currently due from customers and are presented net of an estimate for uncollectible accounts. The Company evaluates outstanding receivables to assess collectability. In performing this evaluation, the Company analyzes market trends, economic conditions, the aging of receivables and customer specific risks. Using this information, the Company reserves an amount that it estimates may not be collected. The Company does not require collateral with respect to trade receivables.
Content Rights	Content Rights Content rights principally consist of television series, specials, films and sporting events. Content aired on the Company’s television networks is sourced from a wide range of third-party producers, wholly-owned and equity method investee production studios and sports associations. Content is classified either as produced, coproduced or licensed. The Company owns most or all of the rights to produced content. The Company collaborates with third parties to finance and develop coproduced content, and it retains significant rights to exploit the programs. Licensed content is comprised of films or series that have been previously produced by third parties and the Company retains limited airing rights over a contractual term. Prepaid licensed content includes advance payments for rights to air sporting events that will take place in the future and advance payments for acquired films and television series. Costs of produced and coproduced content consist of development costs, acquired production costs, direct production costs, certain production overhead costs and participation costs. Costs incurred for produced and coproduced content are capitalized if the Company has previously generated revenues from similar content in established markets and the content will be used and revenues will be generated for a period of at least one year. The Company’s coproduction arrangements generally provide for the sharing of production costs. The Company records its costs, but does not record the costs borne by the other party as the Company does not share any associated economics of exploitation. Program licenses typically have fixed terms and require payments during the term of the license. The cost of licensed content is capitalized when the license period for the programs has commenced and the programs are available for air or the Company has paid for the programs. The Company pays in advance of delivery for television series, specials, films and sports rights. Payments made in advance of when the right to air the content is received are recognized as in-production produced, coproduced content or prepaid licensed content. Content distribution, advertising, marketing, general and administrative costs are expensed as incurred. Content amortization expense for each period is recognized based on the revenue forecast model, which approximates the proportion that estimated distribution and advertising revenues for the current period represent in relation to the estimated remaining total lifetime revenues. The Company annually, or on an as needed basis, prepares analyses to support its content amortization expense by network and by region. Critical assumptions used in determining content amortization include: (i) the grouping of content by network, (ii) the application of a quantitative revenue forecast model based on the adequacy of a network's historical data, (iii) determining the appropriate historical periods to utilize and the relative weighting of those historical periods in the revenue forecast model, and (iv) assessing the accuracy of the Company's revenue forecasts. The Company then considers the appropriate application of the quantitative assessment given forecasted content use, expected content investment and market trends. Content use and future revenues may differ from estimates based on changes in expectations related to market acceptance, network affiliate fee rates, advertising demand, the number of cable and satellite television subscribers receiving the Company’s networks, and program usage. Accordingly, the Company continually reviews revenue estimates and planned usage and revises its assumptions if necessary. As part of the Company's annual assessment in determining the film forecast model, the Company compares the calculated amortization rates to those that have been utilized during the year. If the calculated rates do not deviate materially from the applied amortization rates, no adjustment is recorded for the current year amortization expense. The Company allocates the cost of multi-year sports programming arrangements over the contract period to each event or season based on the estimated relative value of each event or season. The result of the revenue forecast model is either an accelerated method or a straight-line amortization method over the estimated useful lives of primarily three to four years for produced, coproduced and licensed content. Amortization of capitalized costs for produced and coproduced content begins when a program has been aired. Amortization of capitalized costs for licensed content commences when the license period begins and the program is available for use. Amortization of sports rights takes place when the content airs. Capitalized content costs are stated at the lower of cost less accumulated amortization or net realizable value. The Company periodically evaluates the net realizable value of content by considering expected future revenue generation. Estimates of future revenues consider historical airing patterns and future plans for airing content, including any changes in strategy. Given the significant estimates and judgments involved, actual demand or market conditions may be less favorable than those projected, requiring a write-down to net realizable value. Development costs for programs that the Company has determined will not be produced, are fully expensed in the period the determination is made. All produced and coproduced content is classified as long-term. The portion of the unamortized licensed content balance, including prepaid sports rights, that will be amortized within one year is classified as a current asset.
Property and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation and impairments. The cost of property and equipment acquired under capital lease arrangements represents the lesser of the present value of the minimum lease payments or the fair value of the leased asset as of the inception of the lease. The Company leases fixed assets and software. Capitalized software costs are for internal use. Capitalization of software costs occurs during the application development stage. Software costs incurred during the preliminary project and post implementation stages are expensed as incurred. Repairs and maintenance expenditures that do not enhance the use or extend the life of property and equipment are expensed as incurred. Depreciation for most property and equipment is recognized using the straight-line method over the estimated useful lives of the assets, which is 15 to 39 years for buildings, three to five years for broadcast equipment, two to five years for capitalized software costs and three to five years for office equipment, furniture, fixtures and other property and equipment. Assets acquired under capital lease arrangements and leasehold improvements are amortized using the straight-line method over the lesser of the estimated useful lives of the assets or the terms of the related leases, which is one to 15 years. Depreciation commences when property or equipment is ready for its intended use.
Goodwill and Indefinite-lived Intangible Assets	Goodwill and Indefinite-lived Intangible Assets Goodwill is allocated to the Company's reporting units, which are its operating segments or one level below its operating segments. The Company evaluates goodwill and other indefinite-lived intangible assets for impairment annually as of November 30 and earlier if an event or other circumstance indicates that we may not recover the carrying value of the asset. If the Company believes that as a result of its qualitative assessment it is more likely than not that the fair value of a reporting unit or other indefinite-lived intangible asset is greater than its carrying amount, the quantitative impairment test is not required. The Company performs a quantitative impairment test every three years, irrespective of the outcome of the Company's qualitative assessment. The quantitative goodwill impairment test is performed using a two-step process. The first step of the process is to compare the fair value of a reporting unit with its carrying amount, including goodwill. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not impaired and the second step of the quantitative impairment test is not necessary. If the carrying amount of a reporting unit exceeds its fair value, the second step of the quantitative goodwill impairment test is required to be performed to measure the amount of impairment loss, if any. The second step of the quantitative goodwill impairment test compares the implied fair value of the reporting unit’s goodwill with the carrying amount of that goodwill. The implied fair value of goodwill is determined in the same manner as the amount of goodwill recognized in a business combination. In other words, the estimated fair value of the reporting unit’s identifiable net assets excluding goodwill is compared to the fair value of the reporting unit as if the reporting unit had been acquired in a business combination and the fair value of the reporting unit was the purchase price paid. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized in an amount equal to that excess. Following a qualitative assessment indicating that it is not more likely than not that the fair value of the indefinite lived intangible asset exceeds its carrying amount, impairment of other intangible assets not subject to amortization involves a comparison of the estimated fair value of the intangible asset with its carrying value. If the carrying value of the intangible asset exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. Determining fair value requires the exercise of judgment about appropriate discount rates, perpetual growth rates and the amount and timing of expected future cash flows.
Long-lived Assets	Long-lived Assets Long-lived assets such as amortizing trademarks, customer lists, other intangible assets, and property and equipment are not required to be tested for impairment annually. Instead, long-lived assets are tested for impairment whenever circumstances indicate that the carrying amount of the asset may not be recoverable, such as when the disposal of such assets is likely or there is an adverse change in the market involving the business employing the related assets. If an impairment analysis is required, the impairment test employed is based on whether the Company’s intent is to hold the asset for continued use or to hold the asset for sale. If the intent is to hold the asset for continued use, the impairment test first requires a comparison of undiscounted future cash flows to the carrying value of the asset. If the carrying value of the asset exceeds the undiscounted cash flows, the asset would not be deemed to be recoverable. Impairment would then be measured as the excess of the asset’s carrying value over its fair value. Fair value is typically determined by discounting the future cash flows associated with that asset. If the intent is to hold the asset for sale and certain other criteria are met, the impairment test involves comparing the asset’s carrying value to its fair value less costs to sell. To the extent the carrying value is greater than the asset’s fair value less costs to sell, an impairment loss is recognized in an amount equal to the difference. Significant judgments used for long-lived asset impairment assessments include identifying the appropriate asset groupings and primary assets within those groupings, determining whether events or circumstances indicate that the carrying amount of the asset may not be recoverable, determining the future cash flows for the assets involved and assumptions applied in determining fair value, which include, reasonable discount rates, growth rates, market risk premiums and other assumptions about the economic environment.
Equity Method Investments, AFS Securities and Cost Method Investments	Equity Method Investments, AFS Securities and Cost Method Investments Equity method investments, AFS securities and cost method investments are reviewed for indicators of other-than-temporary impairment on a quarterly basis. Equity method investments, AFS securities and cost method investments are written down to fair value if there is evidence of a loss in value which is other-than-temporary. The Company estimates the fair value of its investments by considering share price and other publicly available information, recent investee equity transactions, discounted cash flow analysis, recent operating results, comparable public company operating cash flow multiples and in certain situations, balance sheet liquidation values. If the fair value of the investment has dropped below the carrying amount, management considers several factors when determining whether an other-than-temporary decline has occurred, such as: the length of the time and the extent to which the estimated fair value or market value has been below the carrying value, the financial condition and the near-term prospects of the investee, the intent and ability of the Company to retain its investment in the investee for a period of time sufficient to allow for any anticipated recovery in market value and general market conditions. The estimation of fair value and whether an other-than-temporary impairment has occurred requires the application of significant judgment and future results may vary from current assumptions. (See Note 4.) Other than AFS securities, fair values of investments are not assessed every reporting period unless there are indications of impairment. If declines in the value of these investments are determined to be other-than-temporary, a loss is recorded in earnings in the current period as a component of other income (expense), net on the consolidated statements of operations.
Derivative Instruments	Derivative Instruments The Company uses derivative financial instruments to modify its exposure to exogenous events, market risks from changes in foreign currency exchange rates, interest rates, and the fair value of investments classified as available-for-sale securities. At the inception of a derivative contract, the Company designates the derivative as one of four types based on the Company's intentions and expectations as to the likely effectiveness as a hedge. These four types are: (i) a hedge of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability ("cash flow hedge"), (ii) a hedge of net investments in foreign operations ("net investment hedge"), (iii) a hedge of the fair value of a recognized asset or liability or of an unrecognized firm commitment ("fair value hedge"), or (iv) an instrument with no hedging designation. (See Note 10.) Cash Flow Hedges For those derivative instruments designated as cash flow hedges, gains or losses on the effective portion of derivative instruments are initially recorded in accumulated other comprehensive loss on the consolidated balance sheets and reclassified into the consolidated statements of operations in the same line item in which the hedged item is recognized and in the same period as the hedged item affects earnings. If it becomes probable that a forecasted transaction will not occur, any related gains and losses recorded in accumulated other comprehensive loss on the consolidated balance sheets are reclassified to other (expense) income, net on the consolidated statements of operations in that period. Generally, the maximum length of time over which the Company hedges its exposure to variability in future cash flows for forecasted transactions is less than one year. Net Investment Hedges For those derivative instruments designated as net investment hedges, the changes in the fair value of the derivatives instruments are recorded as cumulative translation adjustments, a component of accumulated other comprehensive loss on the consolidated balance sheets, and are only recognized in earnings upon the liquidation or sale of the hedged investment. If the notional amount of the instrument designated as the hedge of a net investment is greater than the portion of the net investment being hedged, hedge ineffectiveness, which is the gain or loss of the portion over-hedged, is reclassified to other (expense) income, net on the consolidated statements of operations in that period. Fair Value Hedges For those derivative instruments designated as fair value hedges, the changes in the fair value of the derivative instruments, including offsetting changes in fair value of the hedged items and amounts excluded from the assessment of effectiveness are recorded in other (expense) income, net . No Hedging Designation The Company may also enter into derivative instruments that are not designated as hedges and do not qualify for hedge accounting. These contracts are intended to mitigate economic exposures of the Company. The changes in fair value of derivatives not designated as hedges and the ineffective portion of derivatives designated as hedging instruments are immediately recorded in other (expense) income, net . Financial Statement Presentation The Company records all unsettled derivative contracts at their gross fair values on the consolidated balance sheets. (See Note 5.) The portion of the fair value that represents cash flows occurring within one year are classified as current, and the portion related to cash flows occurring beyond one year are classified as noncurrent. The cash flows from the effective portion of derivative instruments used as hedges are classified in the consolidated statements of cash flows in the same section as the cash flows from the hedged item. For example, the cash paid or received to settle the effective portion of foreign exchange derivatives intended to hedge distribution revenue earned during the year ended December 31, 2017 is reported as an operating activity in the consolidated statements of cash flows consistent with the classification of cash received from customers. Also, the cash flows related to our interest rate contracts used to hedge the pricing for certain senior notes are reported as a financing activity in the consolidated statements of cash flows consistent with the cash proceeds from our debt offerings. The cash flows from the ineffective portion of derivative instruments used as hedges, periodic settlement of interest on cross-currency swaps, and derivative contracts not designated as hedges are reported as investing activities in the consolidated statements of cash flows.
Treasury Stock	Treasury Stock When stock is acquired for purposes other than formal or constructive retirement, the purchase price of the acquired stock is recorded in a separate treasury stock account, which is separately reported as a reduction of equity. When stock is retired or purchased for formal or constructive retirement, the purchase price is initially recorded as a reduction to the par value of the shares repurchased, with any excess purchase price over par value recorded as a reduction to additional paid-in capital related to the series of shares repurchased and any remainder excess purchase price recorded as a reduction to retained earnings. If the purchase price exceeds the amounts allocated to par value and additional paid-in capital related to the series of shares repurchased and retained earnings, the remainder is allocated to additional paid-in capital related to other series of shares. Common Stock Repurchase Contracts Under common stock repurchase contracts, the Company makes up front cash payments for the future settlement of the contract in either shares or in cash based on the Company's Series C common stock price at settlement in relation to the strike price of the contract. If the Company's Series C common stock price is below the strike price at expiry, the Company receives a predetermined number of its Series C common stock. If the Company's Series C common stock price is above the strike price at expiry, the Company can elect to settle the transaction in either cash or the equivalent value in shares of Series C common stock at the then current market price upon settlement, based on the notional value of the repurchase contract. The contracts represent a hybrid instrument consisting of a debt instrument and an embedded equity-linked derivative that does not require bifurcation because it is linked to the Company’s own stock. The Company accounts for these contracts as equity transactions. Prepayments are recorded as a reduction in additional paid-in capital. If the contract settles in shares of Series C common stock, that amount will be reclassified to treasury stock. If the contract settles in cash, the cash receipt will be recorded as an increase to additional paid-in capital.
Revenue Recognition	Revenue Recognition The Company generates revenues principally from (i) fees charged to distributors of its network content, which include cable, direct-to-home ("DTH") satellite, telecommunications and digital service providers, (ii) advertising sold on its television networks and websites, (iii) transactions for curriculum-based products and services, (iv) production studios content development and services, (v) affiliate and advertising sales representation services and (vi) the licensing of the Company's brands for consumer products. Revenue is recognized when persuasive evidence of a sales arrangement exists, services are rendered or delivery occurs, the sales price is fixed or determinable and collectability is reasonably assured. Revenues do not include taxes collected from customers on behalf of taxing authorities such as sales tax and value-added tax. However, certain revenues include taxes that customers pay to taxing authorities on the Company’s behalf, such as foreign withholding tax. Revenue recognition for each source of revenue is also based on the following policies. Distribution Cable operators, DTH satellite and telecommunications service providers typically pay a per-subscriber fee for the right to distribute the Company’s programming under the terms of distribution contracts. The majority of the Company’s distribution fees are collected monthly throughout the year and distribution revenue is recognized over the term of the contracts based on contracted programming rates and reported subscriber levels. The amount of distribution fees due to the Company are reported by distributors based on actual subscriber levels. Such information is generally not received until after the close of the reporting period. In these cases, the Company estimates the number of subscribers receiving the Company’s programming. Historical adjustments to recorded estimates have not been material. Revenues associated with digital distribution arrangements are recognized when the Company transfers control of the content and the rights to distribute the content to the customer. If multiple programs are included in the arrangement, the Company allocates the fee to each program based on its relative fair value. Advertising Advertising revenues are principally generated from the sale of bundled commercial time on television networks and websites. The Company allocates the ad sales arrangement consideration to each item based on its relative fair value. Advertising revenues are recognized net of agency commissions in the period advertising spots are aired. A substantial portion of the advertising contracts in the U.S. guarantee the advertiser a minimum audience level that either the program in which their advertisements are aired or the advertisement will reach. Revenues are recognized for the actual audience level delivered. The Company provides the advertiser with additional advertising spots in future periods if the guaranteed audience level is not delivered. Revenues are deferred for any shortfall in the guaranteed audience level until the guaranteed audience level is delivered or the rights associated with the guarantee lapse. Audience guarantees are initially developed internally based on planned programming, historical audience levels, the success of pilot programs, and market trends. In the U.S., actual audience and delivery information is published by independent ratings services. In certain instances, the independent ratings information is not received until after the close of the reporting period. In these cases, reported advertising revenue and related deferred revenue are based upon the Company’s estimates of the audience level delivered. Historical adjustments to recorded estimates have not been material. Advertising revenues from online properties are recognized as impressions are delivered or the services are performed. Other Revenue for curriculum-based services is recognized ratably over the contract term as service is provided. Royalties from brand licensing arrangements are earned as products are sold by the licensee. Revenue from the production studios segment is recognized when the content is delivered and available for airing by the customer.
Deferred Revenues	Deferred Revenue Deferred revenue primarily consists of cash received for television advertising for which the advertising spots have not yet fully delivered the ratings guaranteed, product licensing arrangements, advanced billings to subscribers for access to the Company’s curriculum-based streaming services and advanced fees received related to the sublicensing of Olympic rights. The amounts classified as current are expected to be earned within the next year.
Equity-Based Compensation Expense	-Based Compensation Expense The Company has incentive plans under which performance-based restricted stock units (“PRSUs”), service-based restricted stock units (“RSUs”) stock options, stock appreciation rights (“SARs”) are issued. The Company's unit awards plan is no longer active, effective January 1, 2016. Vesting for certain PRSUs is subject to satisfying objective operating performance conditions, while vesting for other PRSUs is based on the achievement of a combination of objective and subjective operating performance conditions. Compensation expense for PRSUs that vest based on achieving objective operating performance conditions is measured based on the fair value of the Company’s Series A and C common stock on the date of grant less actual forfeitures. Compensation expense for PRSUs that vest based on achieving subjective operating performance conditions or in situations where the executive is able to withhold taxes in excess of the minimum statutory requirement, is remeasured at the fair value of the Company’s Series A and Series C common stock, as applicable, less actual forfeitures each reporting period until the date of conversion. Compensation expense for all PRSUs is recognized ratably, following a graded vesting pattern during the vesting period only when it is probable that the operating performance conditions will be achieved. The Company records a cumulative adjustment to compensation expense for PRSUs if there is a change in the determination of whether or not it is probable the operating performance conditions will be achieved. The Company measures the cost of employee services received in exchange for RSUs based on the fair value of the Company’s Series A common stock on the date of grant less actual forfeitures. Compensation expense for RSUs is recognized ratably during the vesting period. Compensation expense for stock options is attributed to expense over the vesting period based on the fair value on the date of grant less actual forfeitures. Compensation expense for stock options is recognized ratably during the vesting period. The Company measures the cost of employee services received in exchange for SARs and unit awards based on the fair value of the award less forfeitures. Because certain SARs and all unit awards are cash-settled, the Company remeasures the fair value of these awards each reporting period until settlement. Compensation expense, including changes in fair value, for SARs and unit awards is recognized during the vesting period in proportion to the requisite service that has been rendered as of the reporting date. For awards with graded vesting, the Company measures fair value and records compensation expense separately for each vesting tranche. The fair values of SARs and stock options are estimated using the Black-Scholes option-pricing model. Because the Black-Scholes option-pricing model requires the use of subjective assumptions, changes in these assumptions can materially affect the fair value of awards. For SARs the expected term is the period from the grant date to the end of the contractual term of the award unless the terms of the award allow for cash-settlement automatically on the date the awards vest, in which case the vesting date is used. For stock options the simplified method is utilized to calculate the expected term, since the Company does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term. The simplified method considers the period from the date of grant through the mid-point between the vesting date and the end of the contractual term of the award. Expected volatility is based on a combination of implied volatilities from traded options on the Company’s common stock and historical realized volatility of the Company’s common stock. The dividend yield is assumed to be zero because the Company has no history of paying cash dividends and no present intention to pay dividends. The risk-free interest rate is based on U.S. Treasury zero-coupon issues with a remaining term equal to the expected term of the award. When recording compensation cost for share-based awards, the Company has the option to estimate the number of awards granted that are expected to be forfeited or use actual forfeitures, in accordance with the March 2016 FASB guidance that simplified how share-based payments are accounted for and presented in the financial statements. On January 1, 2017, the Company adopted the new guidance on a modified retrospective basis to use actual forfeitures in the calculations of share-based compensation expense instead of estimated forfeitures. The Employee Stock Purchase Plan (the “ESPP”) enables eligible employees to purchase shares of the Company’s common stock through payroll deductions or other permitted means. The Company recognizes the fair value of the discount associated with shares purchased under the plan as equity-based compensation expense. Share-based compensation expense is recorded as a component of selling, general and administrative expense. The Company classifies the intrinsic value of SARs that are vested or will become vested within one year as a current liability. Excess tax benefits realized from the exercise of stock options and vested RSUs, PRSUs and the ESPP are reported as cash inflows from operating activities on the consolidated statements of cash flows.
Advertising Costs	Advertising Costs Advertising costs are expensed as promotional services are delivered in selling, general and administrative expenses. Advertising costs paid to third parties totaled $162 million , $166 million and $148 million for 2017 , 2016 and 2015 , respectively.
Income Taxes	Income Taxes Income taxes are recorded using the asset and liability method of accounting for income taxes. Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Deferred taxes are measured using rates the Company expects to apply to taxable income in years in which those temporary differences are expected to reverse. A valuation allowance is provided for deferred tax assets if it is more likely than not such assets will be unrealized. The Company also engages in transactions that make the Company eligible for federal investment tax credits. The Company accounts for federal investment tax credits under the flow-through method, under which the tax benefit generated from an investment tax credit is recorded in the period the credit is generated. From time to time, the Company engages in transactions in which the tax consequences may be uncertain. Significant judgment is required in assessing and estimating the tax consequences of these transactions. The Company prepares and files tax returns based on its interpretation of tax laws and regulations. In the normal course of business, the Company's tax returns are subject to examination by various taxing authorities. Such examinations may result in future tax and interest assessments by these taxing authorities. In determining the Company's tax provision for financial reporting purposes, the Company establishes a reserve for uncertain tax positions unless the Company determines that such positions are more likely than not to be sustained upon examination based on their technical merits, including the resolution of any appeals or litigations processes. There is considerable judgment involved in determining whether positions taken on the Company's tax returns are more likely than not to be sustained. The Company adjusts its tax reserve estimates periodically because of ongoing examinations by, and settlements with, various taxing authorities, as well as changes in tax laws, regulations and interpretations.
Concentrations Risk	Concentrations Risk Customers The Company has long-term contracts with distributors around the world. For the U.S. Networks segment, more than 90% of distribution revenue comes from the 10 largest distributors. For the International Networks segment, approximately 42% of distribution revenue comes from the 10 largest distributors. Agreements in place with the 10 largest cable and satellite operators with the U.S. Networks and International Networks expire at various times from 2018 through 2021 . Although the Company seeks to renew its agreements with its distributors prior to expiration of a contract, a delay in securing a renewal that results in a service disruption, a failure to secure a renewal or a renewal on less favorable terms may have a material adverse effect on the Company’s financial condition and results of operations. Not only could the Company experience a reduction in distribution revenue, but it could also experience a reduction in advertising revenue, as viewership is impacted by affiliate subscriber levels. No individual customer accounted for more than 10% of total consolidated revenues for 2017 , 2016 and 2015 . As of December 31, 2017 and 2016 , the Company’s trade receivables do not represent a significant concentration of credit risk as the customers and markets in which the Company operates are varied and dispersed across many geographic areas. Financial Institutions Cash and cash equivalents are maintained with several financial institutions. The Company has deposits held with banks that exceed the amount of insurance provided on such deposits. Generally, these deposits may be redeemed upon demand and are maintained with financial institutions of reputable credit and, therefore, bear minimal credit risk. In conjunction with the Scripps Networks acquisition, $2.7 billion of proceeds from debt issuances were invested in money market funds, $1.3 billion were invested in time deposit accounts, and the remainder was invested in highly liquid, short-term instruments with original maturities of 90 days or less. These investments are classified as cash and cash equivalents on the balance sheet and are anticipated to be used for the Scripps Networks acquisition; in the interim, the Company has full access to these proceeds. Additionally, the Company has cash and cash equivalents held by its foreign subsidiaries. Under the TCJA, the Company is subject to U.S. taxes for the deemed repatriation of certain cash balances held by foreign corporations. The Company intends to continue to permanently reinvest these funds outside of the U.S., and current plans do not demonstrate a need to repatriate them to fund our U.S. operations. Lender Counterparties There is a risk that the counterparties associated with the Company’s revolving credit facility will not be available to fund as obligated under the terms of the facility and that the Company may, at the time of such unavailability to fund, have limited or no access to the commercial paper market. If funding under the revolving credit facility is unavailable, the Company may have to acquire a replacement credit facility from different counterparties at a higher cost or may be unable to find a suitable replacement. Typically, the Company seeks to manage such risks from its revolving credit facility by contracting with experienced large financial institutions and monitoring the credit quality of its lenders. As of December 31, 2017 , the Company did not anticipate nonperformance by any of its counterparties.

Derivative Financial Instrume32

Derivative Financial Instruments (Policies)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments The Company uses derivative financial instruments to modify its exposure to exogenous events, market risks from changes in foreign currency exchange rates, interest rates, and the fair value of investments classified as available-for-sale securities. At the inception of a derivative contract, the Company designates the derivative as one of four types based on the Company's intentions and expectations as to the likely effectiveness as a hedge. These four types are: (i) a hedge of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability ("cash flow hedge"), (ii) a hedge of net investments in foreign operations ("net investment hedge"), (iii) a hedge of the fair value of a recognized asset or liability or of an unrecognized firm commitment ("fair value hedge"), or (iv) an instrument with no hedging designation. (See Note 10.) Cash Flow Hedges For those derivative instruments designated as cash flow hedges, gains or losses on the effective portion of derivative instruments are initially recorded in accumulated other comprehensive loss on the consolidated balance sheets and reclassified into the consolidated statements of operations in the same line item in which the hedged item is recognized and in the same period as the hedged item affects earnings. If it becomes probable that a forecasted transaction will not occur, any related gains and losses recorded in accumulated other comprehensive loss on the consolidated balance sheets are reclassified to other (expense) income, net on the consolidated statements of operations in that period. Generally, the maximum length of time over which the Company hedges its exposure to variability in future cash flows for forecasted transactions is less than one year. Net Investment Hedges For those derivative instruments designated as net investment hedges, the changes in the fair value of the derivatives instruments are recorded as cumulative translation adjustments, a component of accumulated other comprehensive loss on the consolidated balance sheets, and are only recognized in earnings upon the liquidation or sale of the hedged investment. If the notional amount of the instrument designated as the hedge of a net investment is greater than the portion of the net investment being hedged, hedge ineffectiveness, which is the gain or loss of the portion over-hedged, is reclassified to other (expense) income, net on the consolidated statements of operations in that period. Fair Value Hedges For those derivative instruments designated as fair value hedges, the changes in the fair value of the derivative instruments, including offsetting changes in fair value of the hedged items and amounts excluded from the assessment of effectiveness are recorded in other (expense) income, net . No Hedging Designation The Company may also enter into derivative instruments that are not designated as hedges and do not qualify for hedge accounting. These contracts are intended to mitigate economic exposures of the Company. The changes in fair value of derivatives not designated as hedges and the ineffective portion of derivatives designated as hedging instruments are immediately recorded in other (expense) income, net . Financial Statement Presentation The Company records all unsettled derivative contracts at their gross fair values on the consolidated balance sheets. (See Note 5.) The portion of the fair value that represents cash flows occurring within one year are classified as current, and the portion related to cash flows occurring beyond one year are classified as noncurrent. The cash flows from the effective portion of derivative instruments used as hedges are classified in the consolidated statements of cash flows in the same section as the cash flows from the hedged item. For example, the cash paid or received to settle the effective portion of foreign exchange derivatives intended to hedge distribution revenue earned during the year ended December 31, 2017 is reported as an operating activity in the consolidated statements of cash flows consistent with the classification of cash received from customers. Also, the cash flows related to our interest rate contracts used to hedge the pricing for certain senior notes are reported as a financing activity in the consolidated statements of cash flows consistent with the cash proceeds from our debt offerings. The cash flows from the ineffective portion of derivative instruments used as hedges, periodic settlement of interest on cross-currency swaps, and derivative contracts not designated as hedges are reported as investing activities in the consolidated statements of cash flows.

Redeemable Noncontrolling Int33

Redeemable Noncontrolling Interest (Policies)	12 Months Ended
	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Redeemable noncontrolling interest [Policy Text Block]	Redeemable noncontrolling interests reflected as of the balance sheet date are the greater of the noncontrolling interest balances adjusted for comprehensive income items and distributions or the redemption values including any remeasurement necessary at the period end foreign exchange rates (i.e., the "floor"). Adjustments to the carrying amount of redeemable noncontrolling interests to redemption value as a result of changes in exchange rates are reflected in currency translation adjustments, a component of other comprehensive income (loss) ; however, such currency translation adjustments to redemption value are allocated to Discovery stockholders only. Redeemable noncontrolling interest adjustments of redemption value to the floor are reflected in retained earnings. Any adjustment of redemption value to the floor that reflects a redemption in excess of fair value is included as an adjustment to net (loss) income available to Discovery stockholders in the calculation of earnings per share. There were no current period adjustments to reflect a redemption in excess of fair value. (See Note 17.)

Equity (Policies)

Equity (Policies)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Treasury Stock	Treasury Stock When stock is acquired for purposes other than formal or constructive retirement, the purchase price of the acquired stock is recorded in a separate treasury stock account, which is separately reported as a reduction of equity. When stock is retired or purchased for formal or constructive retirement, the purchase price is initially recorded as a reduction to the par value of the shares repurchased, with any excess purchase price over par value recorded as a reduction to additional paid-in capital related to the series of shares repurchased and any remainder excess purchase price recorded as a reduction to retained earnings. If the purchase price exceeds the amounts allocated to par value and additional paid-in capital related to the series of shares repurchased and retained earnings, the remainder is allocated to additional paid-in capital related to other series of shares. Common Stock Repurchase Contracts Under common stock repurchase contracts, the Company makes up front cash payments for the future settlement of the contract in either shares or in cash based on the Company's Series C common stock price at settlement in relation to the strike price of the contract. If the Company's Series C common stock price is below the strike price at expiry, the Company receives a predetermined number of its Series C common stock. If the Company's Series C common stock price is above the strike price at expiry, the Company can elect to settle the transaction in either cash or the equivalent value in shares of Series C common stock at the then current market price upon settlement, based on the notional value of the repurchase contract. The contracts represent a hybrid instrument consisting of a debt instrument and an embedded equity-linked derivative that does not require bifurcation because it is linked to the Company’s own stock. The Company accounts for these contracts as equity transactions. Prepayments are recorded as a reduction in additional paid-in capital. If the contract settles in shares of Series C common stock, that amount will be reclassified to treasury stock. If the contract settles in cash, the cash receipt will be recorded as an increase to additional paid-in capital.

Earnings Per Share (Policies)

Earnings Per Share (Policies)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share, Policy [Policy Text Block]	In calculating earnings per share, the Company follows the two-class method, which distinguishes between the classes of securities based on the proportionate participation rights of each security type in the Company's undistributed (loss) income. The Company's Series A, B and C common stock and the Series C-1 convertible preferred stock are treated as one class for purposes of applying the two-class method, because they have substantially equal rights and share equally on an as converted basis with respect to (loss) income available to Discovery Communications, Inc.

Reportable Segments (Policies)

Reportable Segments (Policies)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segment Reporting, Policy [Policy Text Block]	The accounting policies of the reportable segments are the same as the Company’s, except that certain inter-segment transactions that are eliminated for consolidation are not eliminated at the segment level. Inter-segment transactions primarily include the purchase of advertising and content between segments.
Adjusted OIBDA [Policy Text Block]	The Company evaluates the operating performance of its segments based on financial measures such as revenues and adjusted operating income before depreciation and amortization (“Adjusted OIBDA”). Adjusted OIBDA is defined as operating income excluding: (i) mark-to-market share-based compensation, (ii) depreciation and amortization, (iii) restructuring and other charges, (iv) certain impairment charges, (v) gains and losses on business and asset dispositions, and (vi) certain inter-segment eliminations related to production studios. In addition, beginning with the quarter ended September 30, 2017, Adjusted OIBDA also excludes incremental third party transaction costs directly related to the Scripps Networks acquisition and planned integration. The Company uses this measure to assess the operating results and performance of its segments, perform analytical comparisons, identify strategies to improve performance and allocate resources to each segment. The Company believes Adjusted OIBDA is relevant to investors because it allows them to analyze the operating performance of each segment using the same metric management uses. The Company excludes mark-to-market share-based compensation, restructuring and other charges, certain impairment charges, gains and losses on business and asset dispositions and Scripps Networks transaction and integration costs from the calculation of Adjusted OIBDA due to their impact on comparability between periods. The Company also excludes depreciation of fixed assets and amortization of intangible assets, as these amounts do not represent cash payments in the current reporting period. Certain corporate expenses are excluded from segment results to enable executive management to evaluate segment performance based upon the decisions of segment executives. As of January 1, 2017, the Company no longer excludes amortization of deferred launch incentives in calculating total Adjusted OIBDA as it is not material. For the years ended December 31, 2017, 2016 and 2015, deferred launch incentives of $3 million , $13 million and $16 million , respectively, were not reflected as an adjustment to the calculation of total Adjusted OIBDA in order to conform to the current presentation. Total Adjusted OIBDA should be considered in addition to, but not a substitute for, operating income, net (loss) income and other measures of financial performance reported in accordance with GAAP.

Summary Of Significant Accoun37

Summary Of Significant Accounting Policies Summary Of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The table below sets forth the impact of the preferred stock modification to the Company's calculated basic earnings per share. Year Ended December 31, 2016 2015 Pre-Exchange: Basic net income per share available to: Series A, B and C common stockholders $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ 3.94 $ 3.18 Post-Exchange: Basic net income per share available to: Series A, B and C common stockholders $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ 38.07 $ 30.74
New Accounting Pronouncements and Changes in Accounting Principles	• The Company evaluated the accounting for awards that are liability-classified and marked-to-market each accounting period and concluded that there is no change to the accounting for those awards.
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 )

Acquisitions And Dispositions (

Acquisitions And Dispositions (Tables)	12 Months Ended
	Dec. 31, 2017
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The stock prices used to determine the equity portion of the consideration in each scenario is based on Discovery Series C common stock price at the low-end and the high-end of the collar (in millions of dollars and shares, except for conversion ratio). Discovery Series C Common Stock (DISCK) Shares to Issue and Total Estimated Consideration to be Paid Minimum Maximum Scripps shares outstanding as of December 31, 2017 130 130 Average Discovery price - Series C common stock $ 22.32 $ 28.70 Conversion ratio 1.2096 0.9408 Discovery Series C common stock to be issued for estimated Scripps shares outstanding 157 122 Total estimated consideration to be paid $ 11,968 $ 11,968
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The preliminary fair value of assets acquired and liabilities assumed, as well as a reconciliation to cash consideration transferred is presented in the table below (in millions). November 30, 2017 Intangible assets $ 295 Content rights 176 Accounts receivable 84 Other assets 26 Other liabilities (230) Net assets acquired $ 351 Goodwill 136 Remeasurement gain on previously held equity interest (33) Carrying value of previously held equity interest (329) Redeemable noncontrolling interest (55) Cash consideration transferred $ 70 The fair value of the assets acquired and liabilities assumed is presented in the table below (in millions). Preliminary September 25, 2017 Measurement Period Adjustments Final September 25, 2017 Goodwill $ 59 $ 16 $ 75 Intangible assets 71 (18 ) 53 Property plant and equipment, net 16 1 17 Other assets acquired 6 — 6 Liabilities assumed (8 ) 1 (7) Net assets acquired $ 144 $ — $ 144
Eurosport [Member]
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The fair value of the assets acquired, liabilities assumed, noncontrolling interests recognized and the remeasurement gains recorded on the previously held equity interests is presented in the table below (in millions). Eurosport France March 31, 2015 Goodwill $ 69 Intangible assets 40 Other assets acquired 25 Cash 35 Removal of TF1 put right 2 Currency translation adjustment (6 ) Remeasurement gain on previously held equity interest (2 ) Liabilities assumed (30 ) Deferred tax liabilities (14 ) Redeemable noncontrolling interest (Note 11) (60 ) Carrying value of previously held equity interest (21 ) Net assets acquired $ 38

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Investments [Abstract]
Schedule Of Investments	The Company’s investments consisted of the following (in millions). December 31, Category Balance Sheet Location 2017 2016 Cash equivalents: Time deposits Cash and cash equivalents $ 1,305 $ — Trading securities: Money market funds Cash and cash equivalents 2,707 — Mutual funds Prepaid expenses and other current assets 182 160 Equity method investments: Equity investments Equity method investments 335 246 OWN advances and note receivable Equity method investments — 311 AFS securities: Common stock Other noncurrent assets 82 64 Common stock - pledged Other noncurrent assets 82 64 Cost method investments Other noncurrent assets 295 245 Total investments $ 4,988 $ 1,090
Equity Method Investments	The table set forth below presents selected financial information for investments accounted for under the equity method. Because renewable energy projects discussed above are accounted for under the HLBV equity method of accounting, the Company's equity method losses do not directly correlate with the GAAP results of the investees presented below. The selected statement of operations information for each of the three years ended December 31, 2017 , 2016 , and 2015 and the selected balance sheet information as of December 31, 2017 and 2016 (in millions). 2017 2016 2015 Selected Statement of Operations Information: Revenues $ 1,780 $ 1,617 $ 1,324 Cost of sales 1,100 998 853 Operating income 76 83 42 Pre-tax income (loss) from continuing operations before extraordinary items 16 (78 ) (42 ) After-tax net loss (27 ) (98 ) (42 ) Net loss attributable to the entity (27 ) (99 ) (42 ) Selected Balance Sheet Information: Current assets $ 1,002 $ 884 Noncurrent assets 1,946 1,646 Current liabilities 701 752 Noncurrent liabilities 1,008 1,177 Redeemable preferred stock 476 — Non-controlling interests 6 8
Available-for-sale Securities	The accumulated amounts associated with the components of the Company's AFS securities, which are included in other non-current assets, are summarized in the table below. December 31, 2017 2016 Cost $ 195 $ 195 Accumulated change in the value of: Hedged AFS recognized in other expense, net (1 ) (19 ) Unhedged AFS recorded in other comprehensive income 32 14 Other-than-temporary impairment of AFS Securities (62 ) (62 ) Carrying value $ 164 $ 128

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Assets And Liabilities	The table below presents assets and liabilities measured at fair value on a recurring basis (in millions). December 31, 2017 Category Balance Sheet Location Level 1 Level 2 Level 3 Total Assets: Cash equivalent: Time deposits Cash and cash equivalents $ — $ 1,305 $ — $ 1,305 Trading securities: Money market funds Cash and cash equivalents 2,707 — — 2,707 Mutual funds Prepaid expenses and other current assets 182 — — 182 AFS securities: Common stock Other noncurrent assets 82 — — 82 Common stock - pledged Other noncurrent assets 82 — — 82 Derivatives: Cash flow hedges: Foreign exchange Prepaid expenses and other current assets — 7 — 7 Net investment hedges: Cross-currency swaps Other noncurrent assets — 3 — 3 Foreign exchange Prepaid expenses and other current assets — 2 — 2 Fair value hedges: Equity (Lionsgate Collar) Other noncurrent assets — 13 — 13 Total $ 3,053 $ 1,330 $ — $ 4,383 Liabilities: Deferred compensation plan Accrued liabilities $ 182 $ — $ — $ 182 Derivatives: Cash flow hedges: Foreign exchange Accrued liabilities — 12 — 12 Net investment hedges: Cross-currency swaps Accrued liabilities — 13 — 13 Cross-currency swaps Other noncurrent liabilities — 98 — 98 Foreign exchange Accrued liabilities — 8 — 8 No hedging designation: Credit contracts Other noncurrent liabilities — 1 — 1 Cross-currency swaps Other noncurrent liabilities — 6 — 6 Total $ 182 $ 138 $ — $ 320 December 31, 2016 Category Balance Sheet Location Level 1 Level 2 Level 3 Total Assets: Trading securities - mutual funds Prepaid expenses and other current assets $ 160 $ — $ — $ 160 Available-for-sale securities: Common stock Other noncurrent assets 64 — — 64 Common stock - pledged Other noncurrent assets 64 — — 64 Derivatives: Cash flow hedges: Foreign exchange Prepaid expenses and other current assets — 31 — 31 Net investment hedges: Cross-currency swaps Other noncurrent assets — 35 — 35 Fair value hedges: Equity (Lionsgate Collar) Other noncurrent assets — 25 — 25 No hedging designation: Cross-currency swaps Other noncurrent assets — 1 — 1 Total $ 288 $ 92 $ — $ 380 Liabilities: Deferred compensation plan Accrued liabilities $ 160 $ — $ — $ 160 Derivatives: Cash flow hedges: Foreign exchange Accrued liabilities — 18 — 18 Net investment hedges: Cross-currency swaps Accrued liabilities — 3 — 3 Cross-currency swaps Other noncurrent liabilities — 31 — 31 Total $ 160 $ 52 $ — $ 212

Content Rights (Tables)

Content Rights (Tables)	12 Months Ended
	Dec. 31, 2017
Content Rights [Abstract]
Schedule Of Content Rights	The following table presents the components of content rights (in millions). December 31, 2017 2016 Produced content rights: Completed $ 4,355 $ 3,920 In-production 442 420 Coproduced content rights: Completed 745 632 In-production 27 57 Licensed content rights: Acquired 1,070 1,090 Prepaid (a) 181 129 Content rights, at cost 6,820 6,248 Accumulated amortization (4,197 ) (3,849 ) Total content rights, net 2,623 2,399 Current portion (410 ) (310 ) Noncurrent portion $ 2,213 $ 2,089
Schedule Of Content Expense	Content expense is included in costs of revenues on the consolidated statements of operations and consisted of the following (in millions). For the year ended December 31, 2017 2016 2015 Content amortization $ 1,878 $ 1,701 $ 1,628 Other production charges 310 272 231 Content impairments (a) 32 72 81 Total content expense $ 2,220 $ 2,045 $ 1,940

Property And Equipment (Tables)

Property And Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Components Of Property And Equipment	Property and equipment consisted of the following (in millions). December 31, 2017 2016 Land, buildings and leasehold improvements $ 363 $ 327 Broadcast equipment 728 607 Capitalized software costs 379 347 Office equipment, furniture, fixtures and other 431 333 Property and equipment, at cost 1,901 1,614 Accumulated depreciation (1,304 ) (1,132 ) Property and equipment, net $ 597 $ 482

Goodwill And Intangible Assets

Goodwill And Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill By Reportable Segment	The carrying value and changes in the carrying value of goodwill attributable to each business unit were as follows (in millions). U.S. Networks International Networks Education and Other Total December 31, 2015 $ 5,287 $ 2,800 $ 77 $ 8,164 Dispositions (Note 3) (22 ) — — (22 ) Foreign currency translation — (92 ) (10 ) (102 ) December 31, 2016 5,265 2,708 67 8,040 Acquisitions (Note 3) 211 7 — 218 Dispositions (Note 3) — — (30 ) (30 ) Impairment of goodwill — (1,327 ) — (1,327 ) Foreign currency translation 2 167 3 172 December 31, 2017 $ 5,478 $ 1,555 $ 40 $ 7,073
Schedule Of Intangible Assets Subject To Amortization	Finite-lived intangible assets consisted of the following (in millions, except years). Weighted Average Amortization Period (Years) December 31, 2017 December 31, 2016 Gross Accumulated Amortization Net Gross Accumulated Amortization Net Intangible assets subject to amortization: Trademarks 10 $ 494 $ (224 ) $ 270 $ 412 $ (165 ) $ 247 Customer relationships 16 2,026 (758 ) 1,268 1,632 (594 ) 1,038 Other 16 118 (50 ) 68 97 (34 ) 63 Total $ 2,638 $ (1,032 ) $ 1,606 $ 2,141 $ (793 ) $ 1,348
Schedule Of Intangible Assets Not Subject To Amortization	Indefinite-lived intangible assets not subject to amortization (in millions): December 31, 2017 2016 Intangible assets not subject to amortization: Trademarks $ 164 $ 164
Amortization Expense For Intangible Assets	Amortization expense relating to intangible assets subject to amortization for each of the next five years and thereafter is estimated to be as follows (in millions). 2018 2019 2020 2021 2022 Thereafter Amortization expense $ 220 $ 203 $ 198 $ 174 $ 147 $ 664

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Outstanding Debt	The Company's commercial paper program is supported by the revolving credit facility described above. The following table presents a summary of the outstanding commercial paper borrowings with maturities of less than 90 days (in millions). For the year ended December 31, 2017 2016 Outstanding debt $ — $ 48 Weighted average interest rate — % 1.2 % The following table presents a summary of the outstanding borrowings under the revolving credit facility (in millions). For the year ended December 31, 2017 2016 Outstanding debt $ 425 $ 550 Outstanding debt denominated in foreign currency — 207 Weighted average interest rate 2.69 % 2.05 % The table below presents the components of outstanding debt (in millions). December 31, 2017 2016 5.625% Senior notes, semi-annual interest, due August 2019 $ 411 $ 500 2.200% Senior notes, semi-annual interest, due September 2019 500 — Floating rate notes, quarterly interest, due September 2019 400 — 5.050% Senior notes, semi-annual interest, due June 2020 789 1,300 4.375% Senior notes, semi-annual interest, due June 2021 650 650 2.375% Senior notes, euro denominated, annual interest, due March 2022 358 314 3.300% Senior notes, semi-annual interest, due May 2022 500 500 2.950% Senior notes, semi-annual interest, due March 2023 1,200 — 3.250% Senior notes, semi-annual interest, due April 2023 350 350 3.800% Senior notes, semi-annual interest, due March 2024 450 — 2.500% Senior notes, sterling denominated, annual interest, due September 2024 538 — 3.450% Senior notes, semi-annual interest, due March 2025 300 300 4.900% Senior notes, semi-annual interest, due March 2026 700 500 1.900% Senior notes, euro denominated, annual interest, due March 2027 717 627 3.950% Senior notes, semi-annual interest, due March 2028 1,700 — 5.000% Senior notes, semi-annual interest, due September 2037 1,250 — 6.350% Senior notes, semi-annual interest, due June 2040 850 850 4.950% Senior notes, semi-annual interest, due May 2042 500 500 4.875% Senior notes, semi-annual interest, due April 2043 850 850 5.200% Senior notes, semi-annual interest, due September 2047 1,250 — Revolving credit facility 425 550 Commercial paper — 48 Capital lease obligations 225 151 Total debt 14,913 7,990 Unamortized discount and debt issuance costs (128 ) (67 ) Debt, net 14,785 7,923 Current portion of debt (30 ) (82 ) Noncurrent portion of debt $ 14,755 $ 7,841
Debt Repayment Schedule	The following table presents a summary of scheduled and estimated debt payments, excluding the revolving credit facility, commercial paper borrowings and capital lease obligations, for the succeeding five years based on the amount of debt outstanding as of December 31, 2017 (in millions). 2018 2019 2020 2021 2022 Thereafter Long-term debt repayments $ — $ 1,311 $ 789 $ 650 $ 858 $ 10,655

Derivative Financial Instrume45

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The following table summarizes the impact of derivative financial instruments on the Company's consolidated balance sheets (in millions). There were no amounts eligible to be offset under master netting agreements as of December 31, 2017 and December 31, 2016 . December 31, 2017 December 31, 2016 Fair Value Fair Value Notional Prepaid expenses and other current assets Other non- current assets Accrued liabilities Other non- current liabilities Notional Prepaid expenses and other current assets Other non- current assets Accrued liabilities Other non- current liabilities Cash flow hedges: Foreign exchange $ 817 $ 7 $ — $ 12 $ — $ 677 $ 31 $ — $ 18 $ — Net investment hedges: (a) Cross-currency swaps 1,708 — 3 13 98 751 — 35 3 31 Foreign exchange 303 2 — 8 — — — — — — Fair value hedges: Equity (Lionsgate collar) 97 — 13 — — 97 — 25 — — No hedging designation: Interest rate swaps 25 — — — — 25 — — — — Cross-currency swaps 64 — — — 6 64 — 1 — — Credit contracts 665 — — — 1 — — — — — Total $ 9 $ 16 $ 33 $ 105 $ 31 $ 61 $ 21 $ 31 (a) Excludes £400 million of sterling notes ( $538 million equivalent at December 31, 2017 ) designated as a net investment hedge. (Note 9.)
Schedule of Derivative Instruments Designated as Cash Flow Hedges, Effect on Other Comprehensive Income (Loss) [Table Text Block]	The following table presents the pretax impact of derivatives designated as cash flow hedges on income and other comprehensive income (loss) (in millions). Year Ended December 31, 2017 2016 2015 (Losses) gains recognized in accumulated other comprehensive loss: Foreign exchange - derivative adjustments $ (41 ) $ (1 ) $ 34 Interest rate swaps - derivative adjustments — 40 (11 ) (Losses) gains reclassified into income from accumulated other comprehensive loss (effective portion): Foreign exchange - distribution revenue (22 ) (25 ) 23 Foreign exchange - advertising revenue (3 ) (2 ) 2 Foreign exchange - costs of revenues — 27 9 Foreign exchange - other (expense) income, net — 3 4 Interest rate - interest expense (1 ) (3 ) (3 ) Gains (losses) reclassified into income from accumulated other comprehensive loss (ineffective portion): Foreign exchange - other (expense) income, net — 1 — Interest rate - other (expense) income, net 17 — (11 ) Fair value excluded from effectiveness assessment: Foreign exchange - other (expense) income, net — (5 ) —
Schedule of Net Investment Hedges in Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The following table presents the pretax impact of derivatives designated as net investment hedges on other comprehensive income (loss) (in millions). Year Ended December 31, 2017 2016 2015 Currency translation adjustments: Cross-currency swaps - changes in fair value $ (109 ) $ 1 $ — Cross-currency swaps - interest settlements 13 2 — Foreign exchange - changes in fair value (18 ) — — Sterling Notes - changes in foreign exchange rates 2 — — Total in other comprehensive income (loss) $ (112 ) $ 3 $ —
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following table presents the pretax impact of derivatives designated as fair value hedges on income, including offsetting changes in fair value of the hedged items and amounts excluded from the assessment of effectiveness (in millions). The Company recognized $1 million of ineffectiveness on fair value hedges for the years ended December 31, 2017 and 2016 . Year Ended December 31, 2017 2016 2015 Gains (losses) on changes in fair value of hedged AFS $ 18 $ (17 ) $ (2 ) (Losses) gains on changes in the intrinsic value of equity contracts (17 ) 16 2 Fair value of equity contracts excluded from effectiveness assessment 5 (6 ) 10 Total in other (expense) income, net $ 6 $ (7 ) $ 10
Schedule of Gains (Losses on Derivatives Not Designated as Hedges [Table Text Block]	The following table presents the pretax (losses) gains on derivatives not designated as hedges and recognized in other (expense) income, net in the consolidated statements of operations (in millions). Year Ended December 31, 2017 2016 2015 Interest rate swaps $ (98 ) $ — $ — Cross-currency swaps (6 ) — — Foreign exchange — (1 ) 6 Credit contracts (1 ) — — Total in other (expense) income, net $ (105 ) $ (1 ) $ 6

Redeemable Noncontrolling Int46

Redeemable Noncontrolling Interest (Tables)	12 Months Ended
	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Redeemable noncontrolling interests [Table Text Block]	The table below presents the reconciliation of changes in redeemable noncontrolling interests (in millions). December 31, 2017 2016 2015 Beginning balance $ 243 $ 241 $ 747 Initial fair value of redeemable noncontrolling interests of acquired businesses 137 — 60 Purchase of subsidiary shares at fair value — — (551 ) Cash distributions to redeemable noncontrolling interests (30 ) (22 ) (42 ) Comprehensive (loss) income adjustments: Net income attributable to redeemable noncontrolling interests 24 23 13 Other comprehensive income (loss) attributable to redeemable noncontrolling interests 1 — (23 ) Currency translation on redemption values — 1 (36 ) Retained earnings adjustments: Adjustments to redemption value 38 — 73 Ending balance $ 413 $ 243 $ 241

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of Stock Repurchases	The table below presents a summary of common stock repurchases (in millions). Year Ended December 31, 2017 2016 2015 Series C Common Stock: Shares repurchased 14.3 34.8 23.7 Purchase price (a) $ 381 $ 895 $ 698 (a) The purchase price for Series C common stock in 2016 includes repurchases made pursuant to a common stock repurchase contract that was executed on August 22, 2016 and settled on December 2, 2016 at a cost of $71 million , resulting in the receipt of 2.8 million shares of Series C common stock at the then current market price equal to $75 million . See below for additional details.
Schedule Of Preferred Stock	The following table summarizes the preferred shares issued at the time of the Exchange. Pre-Exchange Post-Exchange Shares Held Prior to the Amendment Converts into Common Stock Shares Issued Subsequent to the Amendment Converts into Common Stock Series A Preferred Stock 70,673,242 Common A 70,673,242 Series A-1 Preferred Stock 7,852,582 Common A 70,673,242 Common C 70,673,242 Series C-1 Preferred Stock 3,649,573 Common C 70,673,242 Series C Preferred Stock 24,874,370 Common C 49,748,740 Series C-1 Preferred Stock 2,569,020 Common C 49,748,740
Preferred Stock Repurchase	The table below presents a summary of Series C and Series C-1 convertible preferred stock repurchases made under the repurchase agreement (in millions). Year Ended December 31, 2017 2016 Series C Convertible Preferred Stock: Shares repurchased 2.3 9.1 Purchase price $ 120 $ 479 Series C-1 Convertible Preferred Stock: Shares repurchased 0.2 — Purchase price $ 102 $ —
Schedule of Other Comprehensive (Loss) Income	The table below presents the tax effects related to each component of other comprehensive income (loss) and reclassifications made into the consolidated statements of operations (in millions). Year Ended December 31, 2017 Year Ended December 31, 2016 Year Ended December 31, 2015 Pretax Tax Benefit (Expense) Net-of-tax Pretax Tax Benefit (Expense) Net-of-tax Pretax Tax Benefit (Expense) Net-of-tax Currency translation adjustments: Unrealized gains (losses) Foreign currency $ 280 $ 3 $ 283 $ (234 ) $ 41 $ (193 ) $ (249 ) $ 19 $ (230 ) Net investment hedges (112 ) — (112 ) 3 (1 ) 2 — — — Reclassifications: Loss (gain) on disposition 12 — 12 — — — 23 — 23 Other (expense) income, net — — — — — — 6 — 6 Total currency translation adjustments 180 3 183 (231 ) 40 (191 ) (220 ) 19 (201 ) AFS adjustments: Unrealized gains (losses) 36 (6 ) 30 (34 ) 6 (28 ) (33 ) 6 (27 ) Reclassifications to other (expense) income, net: Other-than-temporary-impairment AFS securities — — — 62 (10 ) 52 — — — Hedged portion of AFS securities (18 ) 3 (15 ) 17 (3 ) 14 2 — 2 Total AFS adjustments 18 (3 ) 15 45 (7 ) 38 (31 ) 6 (25 ) Derivative adjustments: Unrealized (losses) gains (41 ) 15 (26 ) 39 (14 ) 25 23 (8 ) 15 Reclassifications: Distribution revenue 22 (8 ) 14 25 (7 ) 18 (23 ) 8 (15 ) Advertising revenue 3 (1 ) 2 2 — 2 (2 ) — (2 ) Costs of revenues — — — (27 ) 7 (20 ) (9 ) 3 (6 ) Interest expense 1 — 1 3 (1 ) 2 3 (1 ) 2 Other (expense) income, net (17 ) 6 (11 ) (4 ) 1 (3 ) 7 (2 ) 5 Total derivative adjustments (32 ) 12 (20 ) 38 (14 ) 24 (1 ) — (1 ) Other comprehensive income (loss) $ 166 $ 12 $ 178 $ (148 ) $ 19 $ (129 ) $ (252 ) $ 25 $ (227 )
Schedule Of Change In Components Of Accumulated Other Comprehensive (Loss) Income	The table below presents the changes in the components of accumulated other comprehensive loss, net of taxes (in millions). Currency Translation Adjustments AFS Derivative Adjustments Accumulated Other Comprehensive Loss December 31, 2014 $ (367 ) $ (2 ) $ 1 $ (368 ) Other comprehensive (loss) income before reclassifications (230 ) (27 ) 15 (242 ) Reclassifications from accumulated other comprehensive loss to net income 29 2 (16 ) 15 Other comprehensive loss (201 ) (25 ) (1 ) (227 ) Purchase of redeemable noncontrolling interest (61 ) — — (61 ) Other comprehensive loss attributable to redeemable noncontrolling interests 23 — — 23 December 31, 2015 (606 ) (27 ) — (633 ) Other comprehensive (loss) income before reclassifications (191 ) (28 ) 25 (194 ) Reclassifications from accumulated other comprehensive loss to net income — 66 (1 ) 65 Other comprehensive (loss) income (191 ) 38 24 (129 ) December 31, 2016 (797 ) 11 24 (762 ) Other comprehensive income (loss) before reclassifications 171 30 (26 ) 175 Reclassifications from accumulated other comprehensive loss to net loss 12 (15 ) 6 3 Other comprehensive income (loss) 183 15 (20 ) 178 Other comprehensive income attributable to redeemable noncontrolling interests (1 ) — — (1 ) December 31, 2017 $ (615 ) $ 26 $ 4 $ (585 )

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	The table below presents the components of share-based compensation expense (in millions). Year Ended December 31, 2017 2016 2015 RSUs $ 23 $ 17 $ 17 Stock options 12 13 17 PRSUs 6 34 16 SARs (3 ) 4 (14 ) ESPP 1 1 1 Unit awards — — (2 ) Total share-based compensation expense $ 39 $ 69 $ 35 Tax benefit recognized $ 9 $ 25 $ 13
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Scheduled Of Weighted-Average Assumptions Used To Determine Fair Value Of Stock Options	The fair value of stock options is estimated using the Black-Scholes option-pricing model. The weighted-average assumptions used to determine the fair value of stock options as of the date of grant during 2017 , 2016 and 2015 were as follows. Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.87 % 1.26 % 1.54 % Expected term (years) 5.0 5.0 5.0 Expected volatility 27.52 % 28.74 % 26.78 % Dividend yield — — —
Stock-Based Compensation - Summary Of Activities	The table below presents stock option activity (in millions, except years and weighted-average exercise price). Stock Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding as of December 31, 2016 13.7 $ 26.05 Granted 2.6 $ 28.74 Exercised (2.5 ) $ 17.54 $ 26 Forfeited (1.5 ) $ 33.46 Outstanding as of December 31, 2017 12.3 $ 27.46 3.5 14 Vested and expected to vest as of December 31, 2017 12.3 $ 27.46 3.5 14 Exercisable as of December 31, 2017 6.7 $ 26.26 2.1 14
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation - Summary Of Activities	The table below presents RSU activity (in millions, except years and weighted-average grant price). RSUs Weighted-Average Grant Price Weighted-Average Remaining Contractual Term (years) Aggregate Fair Value Outstanding as of December 31, 2016 2.6 $ 30.03 Granted 1.6 $ 28.81 Converted (0.4 ) $ 35.91 $ 12 Forfeited (0.4 ) $ 29.61 Outstanding as of December 31, 2017 3.4 $ 28.78 2.6 $ 77 Vested and expected to vest as of December 31, 2017 3.4 $ 28.78 2.6 $ 77
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation - Summary Of Activities	The table below presents PRSU activity (in millions, except years and weighted-average grant price). PRSUs Weighted-Average Grant Price Weighted-Average Remaining Contractual Term (years) Aggregate Fair Value Outstanding as of December 31, 2016 4.5 $ 34.44 Granted 0.7 $ 29.50 Converted (1.7 ) $ 34.62 $ 49 Forfeited — $ — Outstanding as of December 31, 2017 3.5 $ 33.41 0.9 76 Vested and expected to vest as of December 31, 2017 3.5 $ 33.41 0.9 76 Convertible as of December 31, 2017 1.5 $ 40.42 — 33
SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation - Summary Of Activities	The table below presents SAR award activity (in millions, except years and weighted-average grant price). SARs Weighted- Average Grant Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding as of December 31, 2016 8.6 $ 35.29 Granted 3.0 $ 27.39 Settled (0.6 ) $ 25.72 $ 1 Forfeited (3.3 ) $ 38.60 Outstanding as of December 31, 2017 7.7 $ 31.58 1.0 $ — Vested and expected to vest as of December 31, 2017 7.7 $ 31.58 1.0 $ —
Scheduled Of Weighted-Average Assumptions Used To Determine, Fair Value Of SARs	The fair value of outstanding SARs is estimated using the Black-Scholes option-pricing model. The weighted-average assumptions used to determine the fair value of outstanding SARs were as follows. Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.74 % 0.95 % 0.83 % Expected term (years) 1.0 0.9 0.9 Expected volatility 31.37 % 29.46 % 31.59 % Dividend yield — — —

Restructuring And Other Charg49

Restructuring And Other Charges (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Other Charges, By Reporting Segment	Restructuring and other charges, by reportable segment were as follows (in millions). Year Ended December 31, 2017 2016 2015 U.S. Networks $ 18 $ 15 $ 33 International Networks 42 26 14 Education and Other 3 3 2 Corporate 12 14 1 Total restructuring and other charges $ 75 $ 58 $ 50
Total Restructuring And Other Charges	Year Ended December 31, 2017 2016 2015 Restructuring charges $ 68 $ 55 $ 29 Other charges 7 3 21 Total restructuring and other charges $ 75 $ 58 $ 50
Changes In Exit And Restructuring Liabilities	Changes in restructuring and other liabilities by major category were as follows (in millions). Contract Terminations Employee Relocations/ Terminations Total December 31, 2014 $ 4 $ 15 $ 19 Net accruals 3 26 29 Cash paid (5 ) (20 ) (25 ) December 31, 2015 2 21 23 Net accruals 3 52 55 Cash paid (2 ) (37 ) (39 ) December 31, 2016 3 36 39 Net accruals 3 65 68 Cash paid (5 ) (59 ) (64 ) December 31, 2017 $ 1 $ 42 $ 43

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	INCOME TAXES The domestic and foreign components of income before income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Domestic $ 815 $ 1,414 $ 1,281 Foreign (952 ) 257 278 Income before income taxes $ (137 ) $ 1,671 $ 1,559 The components of the provision for income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Current: Federal $ 177 $ 384 $ 306 State and local 45 (56 ) 57 Foreign 153 152 146 375 480 509 Deferred: Federal (124 ) 45 59 State and local (7 ) — (10 ) Foreign (68 ) (72 ) (47 ) (199 ) (27 ) 2 Income taxes $ 176 $ 453 $ 511 On December 22, 2017, new federal tax reform legislation was enacted in the United States, resulting in significant changes from previous tax law. The TCJA revised the U.S. corporate income tax by among other things, lowering the statutory corporate tax rate from 35% to 21% and reinstating bonus depreciation that will allow for full expensing of qualified property, for property placed in service before 2023, including qualified film. The TCJA also eliminated or significantly amended certain deductions (interest, domestic production activities deduction and executive compensation). The TCJA fundamentally changed taxation of multinational entities by moving from a system of worldwide taxation with deferral to a hybrid territorial system, featuring a participation exemption regime with current taxation of certain foreign income. Included in the international provisions was the enactment of a minimum tax on low-taxed foreign earnings, and new measures to deter base erosion and promote U.S. production. In addition, the TCJA imposed a mandatory repatriation toll tax on unremitted foreign earnings. Notwithstanding the U.S. taxation of these amounts, we intend to continue to invest most or all of these earnings, as well as our capital in these subsidiaries, indefinitely outside of the U.S. and do not expect to incur any significant, additional taxes related to such amounts. To the extent that a company’s accounting for certain income tax effects of the TCJA is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate in the financial statements and the TCJA provides a measurement period that should not extend beyond one year from the TCJA enactment date. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply the tax laws that were in effect immediately before the enactment of the TCJA. Although not effective until January 1, 2018, the Company has calculated its best estimate of the TCJA impact in its year end income tax provision and as a result has recorded $44 million as an income tax benefit. Our federal income tax expense for periods beginning in 2018 will be based on the new rate. The mandatory repatriation toll charge resulted in a tax expense which was mostly offset by available foreign tax credits. We have recorded provisional amounts for several of the impacts of the new tax law including: the deemed repatriation tax on post-1986 accumulated earnings and profits, the deferred tax rate change effect of the new law, gross foreign tax credit carryforwards and related valuation allowances to offset foreign tax credit carryforwards. Certain items or estimates that result in impacts of the TCJA being provisional include: detailed foreign earnings calculations for the most recent period, projected foreign cash balances for certain foreign subsidiaries and finalized computations of foreign tax credit availability. In addition, our 2017 US federal income tax return will not be finalized until later in 2018, and while historically this process has resulted in offsetting changes in estimates in current and deferred taxes for items which are timing related, the reduction of the US tax rate will result in adjustments to our income tax provision when recorded. Finally, we consider it likely that further technical guidance regarding certain of the new provisions included in the TCJA, as well as clarity regarding state income tax conformity to current federal tax code, may be issued. We have reported provisional amounts for the income tax effects of the TCJA for which the accounting is incomplete but a reasonable estimate could be determined. Based on a continued analysis of the estimates and further guidance and interpretations on the application of the law, additional revisions may occur throughout the allowable measurement period. The following table reconciles the Company's effective income tax rate to the U.S. federal statutory income tax rate of 35% . Year Ended December 31, 2017 2016 2015 U.S. federal statutory income tax rate 35 % 35 % 35 % State and local income taxes, net of federal tax benefit (18 )% (2 )% 2 % Effect of foreign operations 25 % (1 )% 1 % Domestic production activity deductions 39 % (4 )% (3 )% Change in uncertain tax positions (44 )% — % (1 )% Preferred stock modification (9 )% — % — % Goodwill impairment (334 )% — % — % Renewable energy investments tax credits 142 % (1 )% — % Impact of Tax Reform Act 32 % — % — % Other, net 4 % — % (1 )% Effective income tax rate (128 )% 27 % 33 % Income tax expense was $176 million and $453 million and our effective tax rate was (128)% and 27% for 2017 and 2016 , respectively. During 2017, the decrease in the effective tax rate was primarily attributable to the impact of a goodwill impairment charge that is non-deductible for tax purposes. Thereafter, the decrease in the effective tax rate was primarily due to investment tax credits that we receive related to our renewable energy investments, and to a lesser extent, the domestic production activity deduction benefit, the allocation and taxation of income among multiple foreign and domestic jurisdictions, and the impact of the TCJA. The benefits were partially offset by an increase in reserves for uncertain tax positions in 2017. In 2016, we favorably resolved multi-year state tax positions that resulted in a reduction of reserves related to uncertain tax positions that did not recur in 2017. Components of deferred income tax assets and liabilities were as follows (in millions). December 31, 2017 2016 Deferred income tax assets: Accounts receivable $ 5 $ 2 Tax attribute carry-forward 151 67 Accrued liabilities and other 190 174 Total deferred income tax assets 346 243 Valuation allowance (105 ) (25 ) Net deferred income tax assets 241 218 Deferred income tax liabilities: Intangible assets (315 ) (384 ) Content rights (82 ) (166 ) Equity method investments (68 ) (76 ) Notes receivable (3 ) (7 ) Other (28 ) (32 ) Total deferred income tax liabilities (496 ) (665 ) Net deferred income tax liabilities $ (255 ) $ (447 ) The Company’s net deferred income tax assets and liabilities were reported on the consolidated balance sheets as follows (in millions). December 31, 2017 2016 Noncurrent deferred income tax assets (included within other noncurrent assets) $ 64 $ 20 Deferred income tax liabilities (classified on the balance sheet) (319 ) (467 ) Net deferred income tax liabilities $ (255 ) $ (447 ) The Company’s loss carry-forwards were reported on the consolidated balance sheets as follows (in millions). State Foreign Loss carry-forwards $ 176 $ 1,109 Deferred tax asset related to loss carry-forwards 12 61 Valuation allowance against loss carry-forwards (11 ) (17 ) Earliest expiration date of loss carry-forwards 2018 2018 A reconciliation of the beginning and ending amounts of unrecognized tax benefits (without related interest and penalty amounts) is as follows (in millions). Year Ended December 31, 2017 2016 2015 Beginning balance $ 117 $ 173 $ 176 Additions based on tax positions related to the current year 27 13 30 Additions for tax positions of prior years 57 19 17 Additions for tax positions acquired in business combinations — — 3 Reductions for tax positions of prior years — (60 ) (21 ) Settlements (8 ) (16 ) (16 ) Reductions due to lapse of statutes of limitations (6 ) (9 ) (13 ) Changes due to foreign currency exchange rates 2 (3 ) (3 ) Ending balance $ 189 $ 117 $ 173 The balances as of December 31, 2017 , 2016 and 2015 included $189 million , $117 million and $173 million , respectively, of unrecognized tax benefits that, if recognized, would reduce the Company’s income tax expense and effective tax rate after giving effect to interest deductions and offsetting benefits from other tax jurisdictions. For the year ended December 31, 2017 , increases in unrecognized tax benefits related to the uncertainty of allocation and taxation of income among multiple jurisdictions was offset by the movements of tax positions as a result of multiple audit resolutions and lapse of statutes of limitations. The Company and its subsidiaries file income tax returns in the U.S. and various state and foreign jurisdictions. The Internal Revenue Service recently completed audit procedures for its 2008 to 2011 tax years, the results of which should be finalized in the coming year. The Company is currently under audit by the Internal Revenue Service for its 2012 to 2014 consolidated federal income tax returns. It is difficult to predict the final outcome or timing of resolution of any particular tax matter. Accordingly, an estimate of any related impact to the reserve for uncertain tax positions cannot currently be determined. With few exceptions, the Company is no longer subject to audit by any jurisdiction for years prior to 2006. Adjustments that arose from the completion of audits for certain tax years have been included in the change in uncertain tax positions in the table above. It is reasonably possible that the total amount of unrecognized tax benefits related to certain of the Company's uncertain tax positions could decrease by as much as $53 million within the next twelve months as a result of ongoing audits, lapses of statutes of limitations or regulatory developments. As of December 31, 2017 , 2016 and 2015 , the Company had accrued approximately $21 million , $11 million and $20 million , respectively, of total interest and penalties payable related to unrecognized tax benefits. The Company recognizes interest and penalties related to unrecognized tax benefits as a component of income tax expense.
Schedule Of Components Of Income From Continuing Operations Before Income Taxes	The domestic and foreign components of income before income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Domestic $ 815 $ 1,414 $ 1,281 Foreign (952 ) 257 278 Income before income taxes $ (137 ) $ 1,671 $ 1,559
Schedule Of Components Of Provision For Income Taxes	The components of the provision for income taxes were as follows (in millions). Year Ended December 31, 2017 2016 2015 Current: Federal $ 177 $ 384 $ 306 State and local 45 (56 ) 57 Foreign 153 152 146 375 480 509 Deferred: Federal (124 ) 45 59 State and local (7 ) — (10 ) Foreign (68 ) (72 ) (47 ) (199 ) (27 ) 2 Income taxes $ 176 $ 453 $ 511
Schedule Of Effective Income Tax Rate Reconciliation	The following table reconciles the Company's effective income tax rate to the U.S. federal statutory income tax rate of 35% . Year Ended December 31, 2017 2016 2015 U.S. federal statutory income tax rate 35 % 35 % 35 % State and local income taxes, net of federal tax benefit (18 )% (2 )% 2 % Effect of foreign operations 25 % (1 )% 1 % Domestic production activity deductions 39 % (4 )% (3 )% Change in uncertain tax positions (44 )% — % (1 )% Preferred stock modification (9 )% — % — % Goodwill impairment (334 )% — % — % Renewable energy investments tax credits 142 % (1 )% — % Impact of Tax Reform Act 32 % — % — % Other, net 4 % — % (1 )% Effective income tax rate (128 )% 27 % 33 %
Schedule Of Deferred Tax Assets And Liabilities	Components of deferred income tax assets and liabilities were as follows (in millions). December 31, 2017 2016 Deferred income tax assets: Accounts receivable $ 5 $ 2 Tax attribute carry-forward 151 67 Accrued liabilities and other 190 174 Total deferred income tax assets 346 243 Valuation allowance (105 ) (25 ) Net deferred income tax assets 241 218 Deferred income tax liabilities: Intangible assets (315 ) (384 ) Content rights (82 ) (166 ) Equity method investments (68 ) (76 ) Notes receivable (3 ) (7 ) Other (28 ) (32 ) Total deferred income tax liabilities (496 ) (665 ) Net deferred income tax liabilities $ (255 ) $ (447 )
Schedule Of Income Tax Assets And Liabilities Financial Position	The Company’s net deferred income tax assets and liabilities were reported on the consolidated balance sheets as follows (in millions). December 31, 2017 2016 Noncurrent deferred income tax assets (included within other noncurrent assets) $ 64 $ 20 Deferred income tax liabilities (classified on the balance sheet) (319 ) (467 ) Net deferred income tax liabilities $ (255 ) $ (447 )
Summary of Operating Loss Carryforwards [Table Text Block]	The Company’s loss carry-forwards were reported on the consolidated balance sheets as follows (in millions). State Foreign Loss carry-forwards $ 176 $ 1,109 Deferred tax asset related to loss carry-forwards 12 61 Valuation allowance against loss carry-forwards (11 ) (17 ) Earliest expiration date of loss carry-forwards 2018 2018
Schedule Of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amounts of unrecognized tax benefits (without related interest and penalty amounts) is as follows (in millions). Year Ended December 31, 2017 2016 2015 Beginning balance $ 117 $ 173 $ 176 Additions based on tax positions related to the current year 27 13 30 Additions for tax positions of prior years 57 19 17 Additions for tax positions acquired in business combinations — — 3 Reductions for tax positions of prior years — (60 ) (21 ) Settlements (8 ) (16 ) (16 ) Reductions due to lapse of statutes of limitations (6 ) (9 ) (13 ) Changes due to foreign currency exchange rates 2 (3 ) (3 ) Ending balance $ 189 $ 117 $ 173

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Schedule of Income Available to Discovery Stockholders [Table Text Block]	The table below sets forth the computation for (loss) income available to Discovery Communications, Inc. stockholders (in millions). Year Ended December 31, 2017 2016 2015 Numerator: Net (loss) income $ (313 ) $ 1,218 $ 1,048 Less: Allocation of undistributed income to Series A-1 convertible preferred stock 41 (139 ) (113 ) Net income attributable to noncontrolling interests — (1 ) (1 ) Net income attributable to redeemable noncontrolling interests (24 ) (23 ) (13 ) Net (loss) income available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders for basic net income per share $ (296 ) $ 1,055 $ 921 Allocation of net (loss) income available to Discovery Communications Inc. Series A, B and C common stockholders and Series C-1 convertible preferred stockholders for basic net (loss) income per share: Series A, B and C common stockholders (225 ) 789 686 Series C-1 convertible preferred stockholders (71 ) 266 235 Total (296 ) 1,055 921 Add: Allocation of undistributed income to Series A-1 convertible preferred stockholders (41 ) 139 113 Net (loss) income available to Discovery Communications, Inc. Series A, B and C common stockholders for diluted net (loss) income per share $ (337 ) $ 1,194 $ 1,034
Schedule Of Weighted Average Basic And Diluted Shares Outstanding [Table Text Block]	The table below sets forth the Company's calculated (loss) earnings per share. Year Ended December 31, 2017 2016 2015 Basic net (loss) income per share available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders: Series A, B and C common stockholders $ (0.59 ) $ 1.97 $ 1.59 Series C-1 convertible preferred stockholders $ (11.33 ) $ 38.07 $ 30.74 Diluted net (loss) income per share available to Discovery Communications, Inc. Series A, B and C common and Series C-1 convertible preferred stockholders: Series A, B and C common stockholders $ (0.59 ) $ 1.96 $ 1.58 Series C-1 convertible preferred stockholders $ (11.33 ) $ 37.88 $ 30.54 The table below sets forth the weighted average number of shares outstanding utilized in determining the denominator for basic and diluted (loss) earnings per share (in millions). Year Ended December 31, 2017 2016 2015 Denominator - weighted average: Series A, B and C common shares outstanding — basic 384 401 432 Impact of assumed preferred stock conversion 192 206 219 Dilutive effect of share-based awards — 3 5 Series A, B and C common shares outstanding — diluted 576 610 656 Series C-1 convertible preferred stock outstanding — basic and diluted 6 7 8
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	The table below presents the details of the anticipated stock repurchases and share-based awards and that were excluded from the calculation of diluted (loss) earnings per share (in millions). Year Ended December 31, 2017 2016 2015 Anti-dilutive share-based awards 19 8 6 PRSUs whose performance targets have not yet been achieved 2 4 3 Anti-dilutive common stock repurchase contracts — 2 —

Supplemental Disclosures (Table

Supplemental Disclosures (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure Text Block Supplement [Abstract]
Valuation And Qualifying Accounts	Changes in valuation and qualifying accounts consisted of the following (in millions). Beginning of Year Additions Write-offs Utilization End of Year 2017 Allowance for doubtful accounts $ 47 $ 12 $ (4 ) $ — $ 55 Deferred tax valuation allowance 25 84 (4 ) — 105 2016 Allowance for doubtful accounts 40 13 (6 ) — 47 Deferred tax valuation allowance 19 9 (3 ) — 25 2015 Allowance for doubtful accounts 39 8 (7 ) — 40 Deferred tax valuation allowance 13 6 — — 19
Schedule Of Accrued Liabilities	Accrued liabilities consisted of the following (in millions). December 31, 2017 2016 Accrued payroll and related benefits $ 535 $ 486 Content rights payable 219 173 Accrued interest 148 67 Accrued income taxes 45 34 Current portion of share-based compensation liabilities 12 31 Other accrued liabilities 350 284 Total accrued liabilities $ 1,309 $ 1,075
Schedule Of Other Income (Expense), Net	Other (expense) income, net , consisted of the following (in millions). Year Ended December 31, 2017 2016 2015 Foreign currency (losses) gains, net $ (83 ) $ 75 $ (103 ) (Losses) gains on derivative instruments, net (82 ) (12 ) 5 Remeasurement gain on previously held equity interest 33 — 2 Interest income (a) 21 — — Other-than-temporary impairment of AFS investments — (62 ) — Other 1 3 (1 ) Total other (expense) income, net $ (110 ) $ 4 $ (97 )
Schedule of Cash Proceeds Received from Share-based Payment Awards [Table Text Block] (Deprecated 2017-01-31)	Share-Based Plan Payments, net Share-based plan payments, net in the statement of cash flows consisted of the following (in millions). (a) Year Ended December 31, 2017 2016 2015 Tax settlements associated with share-based plans $ (30 ) $ (11 ) $ (27 ) Proceeds from issuance of common stock in connection with share-based plans 46 50 21 Total share-based plan payments, net $ 16 $ 39 $ (6 )
Schedule of Supplemental Cash Flow Information	Supplemental Cash Flow Information Year Ended December 31, 2017 2016 2015 Cash paid for taxes, net (a) $ 274 $ 527 $ 653 Cash paid for interest 357 343 312 Noncash investing and financing activities: Contributions of business and assets of strategic ventures Fair value of assets and liabilities of business received in exchange for redeemable noncontrolling interests (b) 144 — — Fair value of investment received, net of cash paid — 82 — Net asset value of contributed business — 32 — Contingent consideration obligations from business acquisitions — — 13 Accrued purchases of property and equipment 24 42 12 Contingent consideration receivable from business dispositions — — 6 Assets acquired under capital lease arrangements 103 37 5 (a) The decrease in cash paid for taxes, net, is mostly due to the tax benefits from the Company's investments in limited liability companies that sponsor renewable energy projects. (See Note 4.) (b) Amount relates to the Company's VTEN joint venture. (See Note 3.) The joint venture was affected via DCL's contribution of the Velocity network to a newly formed entity, VTEN, which is a non-guarantor subsidiary of the Company and is reflected as a non-cash contribution in the condensed consolidating financial statements. (See Note 23.) The table above does not include the November 30, 2017 acquisition of a controlling interest in OWN from Harpo. The Company increased its ownership stake from 49.50% to 73.99% . The table above does not include the March 31, 2015 acquisition of an additional 31% interest in Eurosport France. The Company increased its ownership stake from 20% to 51% . Upon consolidation a cash payment for a portion of these businesses resulted in inclusion of the fair value of all of the net assets and liabilities of OWN and Eurosport France in Discovery's consolidated financial statements. (See Note 3.)

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Schedule Of Related Party Transactions, Revenues Text Block	The table below presents a summary of the transactions with related parties, including OWN prior to the November 30, 2017 acquisition (in millions). Year Ended December 31, 2017 2016 2015 Revenues and service charges: Liberty Group (a) $ 476 $ 387 $ 171 Equity method investees (b) 145 129 62 Other 46 32 35 Total revenues and service charges $ 667 $ 548 $ 268 Interest income (c) $ 13 $ 17 $ 23 Expenses $ (178 ) $ (102 ) $ (67 ) (a) The increase for the year ended December 31, 2017 reflects the May 2016 acquisition of Time Warner Cable, Inc. by Charter Communications, an equity method investee of the Liberty Group and other changes in the Liberty Group's businesses. (b) The increases to revenue from equity method investees for the years ended December 31, 2017 and 2016 relate to the joint venture agreement with the New Russian Business which began in October 2015. (See Note 3.) (c) The Company records interest earnings from loans to equity method investees as a component of income from equity method investees, net, in the consolidated statements of operations. (See Note 4.)
Schedule Of Related Party Transactions Receivables, Text Block	The table below presents receivables due from related parties (in millions). December 31, 2017 2016 Receivables $ 105 $ 109 Note receivable (a) — 311 (a) The decrease for the year ended December 31, 2017 reflects the November 2017 acquisition of OWN by Discovery (See Note 3.) The receivable is recorded as a component of Discovery's consolidated financial statements.

Commitments And Contingencies (

Commitments And Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule Of Significant Contractual Commitments	As of December 31, 2017 , the Company’s significant contractual commitments, including related payments due by period, were as follows (in millions). Leases Year Ending December 31, Operating Capital Content Other Total 2018 $ 61 $ 48 $ 1,075 $ 332 $ 1,516 2019 52 36 558 241 887 2020 36 33 750 175 994 2021 28 30 342 54 454 2022 17 23 350 29 419 Thereafter 36 95 771 89 991 Total minimum payments 230 265 3,846 920 5,261 Amounts representing interest — (40 ) — — (40 ) Total $ 230 $ 225 $ 3,846 $ 920 $ 5,221

Reportable Segments (Tables)

Reportable Segments (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Schedule Of Revenues By Segment	Year Ended December 31, 2017 2016 2015 U.S. Networks $ 3,434 $ 3,285 $ 3,131 International Networks 3,281 3,040 3,092 Education and Other 158 174 173 Corporate and inter-segment eliminations — (2 ) (2 ) Total revenues $ 6,873 $ 6,497 $ 6,394
Schedule Of Adjusted OIBDA By Segment	Year Ended December 31, 2017 2016 2015 U.S. Networks $ 2,026 $ 1,922 $ 1,774 International Networks 859 835 945 Education and Other 6 (10 ) (2 ) Corporate and inter-segment eliminations (360 ) (334 ) (335 ) Total Adjusted OIBDA $ 2,531 $ 2,413 $ 2,382
Schedule Of Reconciliation Of Adjusted OIBDA To Operating Income	Year Ended December 31, 2017 2016 2015 Net (loss) income available to Discovery Communications, Inc. $ (337 ) $ 1,194 $ 1,034 Net income attributable to redeemable noncontrolling interests 24 23 13 Net income attributable to noncontrolling interests — 1 1 Income tax expense 176 453 511 (Loss) income before income taxes (137 ) 1,671 1,559 Other expense (income), net 110 (4 ) 97 Loss (income) from equity investees, net 211 38 (1 ) Loss on extinguishment of debt 54 — — Interest expense 475 353 330 Operating income 713 2,058 1,985 Loss (gain) on disposition 4 (63 ) 17 Restructuring and other charges 75 58 50 Depreciation and amortization 330 322 330 Impairment of goodwill 1,327 — — Mark-to-market equity-based compensation 3 38 — Scripps Networks transaction and integration costs 79 — — Total Adjusted OIBDA $ 2,531 $ 2,413 $ 2,382
Schedule Of Total Assets By Segment	December 31, 2017 2016 U.S. Networks $ 4,127 $ 3,412 International Networks 5,187 4,922 Education and Other 394 399 Corporate and inter-segment eliminations 12,847 6,939 Total assets $ 22,555 $ 15,672
Schedule Of Content Amortization And Impairment Expense By Segment	Year Ended December 31, 2017 2016 2015 U.S. Networks $ 776 $ 756 $ 771 International Networks 1,126 1,008 931 Education and Other 8 9 7 Total content amortization and impairment expense $ 1,910 $ 1,773 $ 1,709
Schedule Of Revenues By Country	Year Ended December 31, 2017 2016 2015 U.S. $ 3,560 $ 3,411 $ 3,261 Non-U.S. 3,313 3,086 3,133 Total revenues $ 6,873 $ 6,497 $ 6,394
Schedule Of Property And Equipment By Country	December 31, 2017 2016 U.S. $ 309 $ 258 U.K. 173 107 Other 115 117 Total property and equipment, net $ 597 $ 482

Selected Quarterly Financial 56

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Selected Quarterly Financial Information [Abstract]
Selected Quarterly Financial Data (Unaudited)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) 2017 (a, b, c,) 1st quarter 2nd quarter 3rd quarter 4th quarter Revenues $ 1,613 $ 1,745 $ 1,651 $ 1,864 Operating income (loss) 487 630 433 (837 ) Net income (loss) 221 380 223 (1,137 ) Net income (loss) available to Discovery Communications, Inc. 215 374 218 (1,144 ) Earnings per share available to Discovery Communications, Inc. Series A, B and C common stockholders Basic $ 0.37 $ 0.65 $ 0.38 $ (1.99 ) Diluted (e) $ 0.37 $ 0.64 $ 0.38 $ (1.99 ) 2016 (d) 1st quarter 2nd quarter 3rd quarter 4th quarter Revenues $ 1,561 $ 1,708 $ 1,556 $ 1,672 Operating income 489 586 458 525 Net income 269 415 225 309 Net income available to Discovery Communications, Inc. 263 408 219 304 Earnings per share available to Discovery Communications, Inc. Series A, B and C common stockholders Basic $ 0.42 $ 0.66 $ 0.37 $ 0.52 Diluted $ 0.42 $ 0.66 $ 0.36 $ 0.52 (a) Goodwill impairment expense of $1.3 billion was recognized during the fourth quarter of 2017. (See Note 8.) (b) On September 25, 2017 , the Company acquired a 67.5% controlling interest in VTEN, a new joint venture with GoldenTree, in exchange for its contribution of the Velocity network. On November 30, 2017 , the Company acquired a controlling interest in OWN from Harpo, increasing Discovery’s ownership stake from 49.50% to 73.99% . Discovery paid $70 million in cash and recognized a gain of $33 million to account for the difference between the carrying value and the fair value of the previously held 49.50% equity interest. On April 28, 2017 , the Company sold Raw and Betty to All3Media and recorded a loss of $4 million upon disposition. (See Note 3.) As of December 31, 2017 , the Company has incurred transaction and integration costs for the Scripps Networks acquisition of $79 million , including the $35 million charge associated with the modification of Advance/Newhouse's preferred stock. (See Note 12.) (c ) In March 2017, DCL completed a cash tender offer for $600 million aggregate principal amount of DCL's 5.05% senior notes due 2020 and 5.625% senior notes due 2019 . This transaction resulted in a pretax loss on extinguishment of debt of $54 million for the year ended December 31, 2017 , which is presented as a separate line item on the Company's consolidated statements of operations and recognized as a component of financing cash outflows on the consolidated statements of cash flows. The loss included $50 million for premiums to par value, $2 million of non-cash write-offs of unamortized deferred financing costs, $1 million for the write-off of the original issue discount of these senior notes and $1 million accrued for other third-party fees. (See Note 10.) (d) On September 30, 2016, the Company recorded an other-than-temporary impairment of $62 million related to its investment in Lionsgate. On December 2, 2016, the Company acquired a 39% minority interest in Group Nine Media, a newly formed media holding company, in exchange for contributions of $100 million and the Company's digital businesses Seeker and SourceFed, resulting in a gain of $50 million upon deconsolidation of the businesses. (See Note 3.) (e) Amounts may not sum to annual total due to rounding.

Condensed Consolidating Finan57

Condensed Consolidating Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Consolidating Balance Sheet	CONDENSED CONSOLIDATING BALANCE SHEET December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and ASSETS Current assets: Cash and cash equivalents $ — $ — $ 6,800 $ 509 $ — $ — $ 7,309 Receivables, net — — 410 1,428 — — 1,838 Content rights, net — — 4 406 — — 410 Prepaid expenses and other current assets 49 32 204 149 — — 434 Inter-company trade receivables, net — — 205 — — (205 ) — Total current assets 49 32 7,623 2,492 — (205 ) 9,991 Investment in and advances to subsidiaries 4,563 4,532 6,951 — 3,056 (19,102 ) — Noncurrent content rights, net — — 672 1,541 — — 2,213 Goodwill, net — — 3,677 3,396 — — 7,073 Intangible assets, net — — 259 1,511 — — 1,770 Equity method investments — — 25 310 — — 335 Other noncurrent assets, including property and equipment, net — 20 364 809 — (20 ) 1,173 Total assets $ 4,612 $ 4,584 $ 19,571 $ 10,059 $ 3,056 $ (19,327 ) $ 22,555 LIABILITIES AND EQUITY Current liabilities: Current portion of debt $ — $ — $ 7 $ 23 $ — $ — $ 30 Other current liabilities — — 572 1,269 — — 1,841 Inter-company trade payables, net — — — 205 — (205 ) — Total current liabilities — — 579 1,497 — (205 ) 1,871 Noncurrent portion of debt — — 14,163 592 — — 14,755 Other noncurrent liabilities 2 — 297 606 21 (20 ) 906 Total liabilities 2 — 15,039 2,695 21 (225 ) 17,532 Redeemable noncontrolling interests — — — 413 — — 413 Total equity 4,610 4,584 4,532 6,951 3,035 (19,102 ) 4,610 Total liabilities and equity $ 4,612 $ 4,584 $ 19,571 $ 10,059 $ 3,056 $ (19,327 ) $ 22,555 CONDENSED CONSOLIDATING BALANCE SHEET December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and ASSETS Current assets: Cash and cash equivalents $ — $ — $ 20 $ 280 $ — $ — $ 300 Receivables, net — — 421 1,074 — — 1,495 Content rights, net — — 8 302 — — 310 Prepaid expenses and other current assets 62 36 180 119 — — 397 Inter-company trade receivables, net — — 195 — — (195 ) — Total current assets 62 36 824 1,775 — (195 ) 2,502 Investment in and advances to subsidiaries 5,106 5,070 7,450 — 3,417 (21,043 ) — Noncurrent content rights, net — — 663 1,426 — — 2,089 Goodwill, net — — 3,769 4,271 — — 8,040 Intangible assets, net — — 272 1,240 — — 1,512 Equity method investments, including note receivable — — 30 527 — — 557 Other noncurrent assets, including property and equipment, net — 20 306 666 — (20 ) 972 Total assets $ 5,168 $ 5,126 $ 13,314 $ 9,905 $ 3,417 $ (21,258 ) $ 15,672 LIABILITIES AND EQUITY Current liabilities: Current portion of debt $ — $ — $ 52 $ 30 $ — $ — $ 82 Other current liabilities — — 516 963 — — 1,479 Inter-company trade payables, net — — — 195 — (195 ) — Total current liabilities — — 568 1,188 — (195 ) 1,561 Noncurrent portion of debt — — 7,315 526 — — 7,841 Other noncurrent liabilities 1 — 361 498 20 (20 ) 860 Total liabilities 1 — 8,244 2,212 20 (215 ) 10,262 Redeemable noncontrolling interests — — — 243 — — 243 Total equity 5,167 5,126 5,070 7,450 3,397 (21,043 ) 5,167 Total liabilities and equity $ 5,168 $ 5,126 $ 13,314 $ 9,905 $ 3,417 $ (21,258 ) $ 15,672
Condensed Consolidating Statement Of Operations	CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,988 $ 4,897 $ — $ (12 ) $ 6,873 Costs of revenues, excluding depreciation and amortization — — 467 2,191 — (2 ) 2,656 Selling, general and administrative 53 — 309 1,416 — (10 ) 1,768 Impairment of goodwill — — — 1,327 — — 1,327 Depreciation and amortization — — 42 288 — — 330 Restructuring and other charges — — 35 40 — — 75 Loss on disposition — — — 4 — — 4 Total costs and expenses 53 — 853 5,266 — (12 ) 6,160 Operating (loss) income (53 ) — 1,135 (369 ) — — 713 Equity in loss of subsidiaries (288 ) (288 ) (541 ) — (192 ) 1,309 — Interest expense — — (448 ) (27 ) — — (475 ) Loss on extinguishment of debt — — (54 ) — — — — (54 ) Loss from equity investees, net — — (3 ) (208 ) — — (211 ) Other (expense) income, net — — (204 ) 94 — — (110 ) Loss before income taxes (341 ) (288 ) (115 ) (510 ) (192 ) 1,309 (137 ) Income tax benefit (expense) 4 — (173 ) (7 ) — — (176 ) Net loss (337 ) (288 ) (288 ) (517 ) (192 ) 1,309 (313 ) Net income attributable to redeemable noncontrolling interests — — — — — (24 ) (24 ) Net loss available to Discovery Communications, Inc. $ (337 ) $ (288 ) $ (288 ) $ (517 ) $ (192 ) $ 1,285 $ (337 ) CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,963 $ 4,547 $ — $ (13 ) $ 6,497 Costs of revenues, excluding depreciation and amortization — — 466 1,970 — (4 ) 2,432 Selling, general and administrative 14 — 292 1,393 — (9 ) 1,690 Depreciation and amortization — — 41 281 — — 322 Restructuring and other charges — — 28 30 — — 58 Gain on disposition — — (50 ) (13 ) — — (63 ) Total costs and expenses 14 — 777 3,661 — (13 ) 4,439 Operating (loss) income (14 ) — 1,186 886 — — 2,058 Equity in earnings of subsidiaries 1,203 1,203 602 — 802 (3,810 ) — Interest expense — — (332 ) (21 ) — — (353 ) Loss from equity investees, net — — (3 ) (35 ) — — (38 ) Other income (expense), net — — 40 (36 ) — — 4 Income before income taxes 1,189 1,203 1,493 794 802 (3,810 ) 1,671 Income tax benefit (expense) 5 — (290 ) (168 ) — — (453 ) Net income 1,194 1,203 1,203 626 802 (3,810 ) 1,218 Net income attributable to noncontrolling interests — — — — — (1 ) (1 ) Net income attributable to redeemable noncontrolling interests — — — — — (23 ) (23 ) Net income available to Discovery Communications, Inc. $ 1,194 $ 1,203 $ 1,203 $ 626 $ 802 $ (3,834 ) $ 1,194 CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS For the Year Ended December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Revenues $ — $ — $ 1,909 $ 4,498 $ — $ (13 ) $ 6,394 Costs of revenues, excluding depreciation and amortization — — 500 1,847 — (4 ) 2,343 Selling, general and administrative 15 — 265 1,398 — (9 ) 1,669 Depreciation and amortization — — 35 295 — — 330 Restructuring and other charges — — 28 22 — — 50 Loss on disposition — — — 17 — — 17 Total costs and expenses 15 — 828 3,579 — (13 ) 4,409 Operating (loss) income (15 ) — 1,081 919 — — 1,985 Equity in earnings of subsidiaries 1,044 1,044 505 — 696 (3,289 ) — Interest expense — — (318 ) (12 ) — — (330 ) Income (loss) from equity investees, net — — 4 (3 ) — — 1 Other income (expense), net — — 9 (106 ) — — (97 ) Income before income taxes 1,029 1,044 1,281 798 696 (3,289 ) 1,559 Income tax benefit (expense) 5 — (237 ) (279 ) — — (511 ) Net income 1,034 1,044 1,044 519 696 (3,289 ) 1,048 Net income attributable to noncontrolling interests — — — — — (1 ) (1 ) Net loss attributable to redeemable noncontrolling interests — — — — — (13 ) (13 ) Net income available to Discovery Communications, Inc. $ 1,034 $ 1,044 $ 1,044 $ 519 $ 696 $ (3,303 ) $ 1,034
Condensed Consolidating Statement Of Comprehensive Income	CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE (LOSS) INCOME For the Year Ended to December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net loss $ (337 ) $ (288 ) $ (288 ) $ (517 ) $ (192 ) $ 1,309 $ (313 ) Other comprehensive (loss) income, net of tax: Currency translation 183 183 183 186 122 (674 ) 183 Available-for-sale securities 15 15 15 15 10 (55 ) 15 Derivatives (20 ) (20 ) (20 ) (9 ) (13 ) 62 (20 ) Comprehensive loss (159 ) (110 ) (110 ) (325 ) (73 ) 642 (135 ) Comprehensive income attributable to redeemable noncontrolling interests (1 ) (1 ) (1 ) (1 ) (1 ) (20 ) (25 ) Comprehensive loss attributable to Discovery Communications, Inc. $ (160 ) $ (111 ) $ (111 ) $ (326 ) $ (74 ) $ 622 $ (160 ) CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME For the Year Ended to December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net income $ 1,194 $ 1,203 $ 1,203 $ 626 $ 802 $ (3,810 ) $ 1,218 Other comprehensive (loss) income, net of tax: Currency translation (191 ) (191 ) (191 ) (190 ) (127 ) 699 (191 ) Available-for-sale securities 38 38 38 38 25 (139 ) 38 Derivatives 24 24 24 22 16 (86 ) 24 Comprehensive income 1,065 1,074 1,074 496 716 (3,336 ) 1,089 Comprehensive income attributable to noncontrolling interests — — — — — (1 ) (1 ) Comprehensive income attributable to redeemable noncontrolling interests (23 ) (23 ) (23 ) (23 ) (15 ) 84 (23 ) Comprehensive income attributable to Discovery Communications, Inc. $ 1,042 $ 1,051 $ 1,051 $ 473 $ 701 $ (3,253 ) $ 1,065 CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME For the Year Ended to December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Net income $ 1,034 $ 1,044 $ 1,044 $ 519 $ 696 $ (3,289 ) $ 1,048 Other comprehensive (loss) income, net of tax: Currency translation (201 ) (201 ) (201 ) (199 ) (134 ) 735 (201 ) Available-for-sale securities (25 ) (25 ) (25 ) (25 ) (17 ) 92 (25 ) Derivatives (1 ) (1 ) (1 ) (3 ) (1 ) 6 (1 ) Comprehensive income 807 817 817 292 544 (2,456 ) 821 Comprehensive income attributable to noncontrolling interests — — — — — (1 ) (1 ) Comprehensive loss attributable to redeemable noncontrolling interests 23 23 23 23 15 (97 ) 10 Comprehensive income attributable to Discovery Communications, Inc. $ 830 $ 840 $ 840 $ 315 $ 559 $ (2,554 ) $ 830
Condensed Consolidating Statement Of Cash Flows	CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2017 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (3 ) $ 3 $ 476 $ 1,153 $ — $ — $ 1,629 Investing Activities Payments for investments — — (45 ) (399 ) — — (444 ) Purchases of property and equipment — — (43 ) (92 ) — — (135 ) Distributions from equity method investees — — — 77 — — 77 Proceeds from dispositions, net of cash disposed — — — 29 — — 29 Payments for derivative instruments, net — — (111 ) 10 — — (101 ) Business acquisitions, net of cash acquired — — — (60 ) — — (60 ) Inter-company distributions — — 42 — — (42 ) — Other investing activities, net — — (1 ) 2 — — 1 Cash used in investing activities — — (158 ) (433 ) — (42 ) (633 ) Financing Activities Commercial paper repayments, net — — (48 ) — — — (48 ) Borrowings under revolving credit facility — — 350 — — — 350 Principal repayments of revolving credit facility — — (475 ) — — — (475 ) Borrowings from debt, net of discount and including premiums — — 7,488 — — — 7,488 Principal repayments of debt, including discount payment and premiums to par value — — (650 ) — — — (650 ) Payments for bridge financing commitment fees — — (40 ) — — — (40 ) Principal repayments of capital lease obligations — — (7 ) (26 ) — — (33 ) Repurchases of stock (603 ) — — — — — (603 ) Cash settlement of common stock repurchase contracts 58 — — — — — 58 Distributions to redeemable noncontrolling interests — — — (30 ) — — (30 ) Share-based plan proceeds, net 16 — — — — — 16 Inter-company distributions — — — (42 ) — 42 — Inter-company contributions and other financing activities, net 532 (3 ) (156 ) (455 ) — — (82 ) Cash provided by (used in) financing activities 3 (3 ) 6,462 (553 ) — 42 5,951 Effect of exchange rate changes on cash and cash equivalents — — — 62 — — 62 Net change in cash and cash equivalents — — 6,780 229 — — 7,009 Cash and cash equivalents, beginning of period — — 20 280 — — 300 Cash and cash equivalents, end of period $ — $ — $ 6,800 $ 509 $ — $ — $ 7,309 CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2016 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (20 ) $ (9 ) $ 249 $ 1,160 $ — $ — $ 1,380 Investing Activities Payments for investments — — (124 ) (148 ) — — (272 ) Purchases of property and equipment — — (18 ) (70 ) — — (88 ) Proceeds from dispositions, net of cash disposed — — — 19 — — 19 Distributions from equity method investees — — — 87 — — 87 Inter-company distributions — — 30 — — (30 ) — Other investing activities, net — — — (2 ) — — (2 ) Cash used in investing activities — — (112 ) (114 ) — (30 ) (256 ) Financing Activities Commercial paper repayments, net — — (45 ) — — — (45 ) Borrowings under revolving credit facility — — 350 263 — — 613 Principal repayments of revolving credit facility — — (225 ) (610 ) — — (835 ) Borrowings from debt, net of discount and including premiums — — 498 — — — 498 Principal repayments of capital lease obligations — — (5 ) (23 ) — — (28 ) Repurchases of stock (1,374 ) — — — — — (1,374 ) Prepayments of common stock repurchase contracts (57 ) — — — — — (57 ) Distributions to redeemable noncontrolling interests — — — (22 ) — — (22 ) Share-based plan proceeds, net 39 — — — — — 39 Hedge of borrowings from debt instruments — — 40 — — — 40 Inter-company distributions — — — (30 ) — 30 — Inter-company contributions and other financing activities, net 1,412 9 (733 ) (701 ) — — (13 ) Cash provided by (used in) financing activities 20 9 (120 ) (1,123 ) — 30 (1,184 ) Effect of exchange rate changes on cash and cash equivalents — — — (30 ) — — (30 ) Net change in cash and cash equivalents — — 17 (107 ) — — (90 ) Cash and cash equivalents, beginning of period — — 3 387 — — 390 Cash and cash equivalents, end of period $ — $ — $ 20 $ 280 $ — $ — $ 300 CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS For the Year Ended December 31, 2015 (in millions) Discovery DCH DCL Non-Guarantor Other Non- Reclassifications Discovery and Operating Activities Cash (used in) provided by operating activities $ (122 ) $ (15 ) $ 427 $ 1,004 $ — $ — $ 1,294 Investing Activities Payments for investments — — (10 ) (262 ) — — (272 ) Purchases of property and equipment — — (17 ) (86 ) — — (103 ) Distributions from equity method investees — — — 87 — — 87 Proceeds from disposition, net of cash disposed — — — 61 — — 61 Payments for derivative instruments, net — — (11 ) 2 — — (9 ) Business acquisitions, net of cash acquired — — — (80 ) — — (80 ) Inter-company distributions — — 37 — — (37 ) — Other investing activities, net — — — 15 — — 15 Cash used in investing activities — — (1 ) (263 ) — (37 ) (301 ) Financing Activities Commercial paper repayments, net — — (136 ) — — — (136 ) Borrowings under revolving credit facility — — — 1,016 — — 1,016 Principal repayments of revolving credit facility — — (13 ) (252 ) — — (265 ) Borrowings from debt, net of discount and including premiums — — 936 — — — 936 Principal repayments of debt, including discount payment and premiums to par value — — (854 ) — — — (854 ) Principal repayments of capital leases obligations — — (5 ) (22 ) — — (27 ) Repurchases of stock (951 ) — — — — — (951 ) Purchase of redeemable noncontrolling interests — — — (548 ) — — (548 ) Distributions to redeemable noncontrolling interests — — — (42 ) — — (42 ) Share-based plan payments, net (6 ) — — — — — (6 ) Hedge of borrowings from debt distributions — — (29 ) — — — (29 ) Inter-company distributions — — — (37 ) — 37 — Inter-company contributions and other financing activities, net 1,079 15 (330 ) (777 ) — — (13 ) Cash provided by (used in) financing activities 122 15 (431 ) (662 ) — 37 (919 ) Effect of exchange rate changes on cash and cash equivalents — — — (51 ) — — (51 ) Net change in cash and cash equivalents — — (5 ) 28 — — 23 Cash and cash equivalents, beginning of period — — 8 359 — — 367 Cash and cash equivalents, end of period $ — $ — $ 3 $ 387 $ — $ — $ 390

Description Of Business And B58

Description Of Business And Basis Of Presentation (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred income taxes		$ 0
Other noncurrent assets	$ 576	490
Deferred income taxes	$ (319)	$ (467)

Summary Of Significant Accoun59

Summary Of Significant Accounting Policies - Preferred Stock Exchange (Details) - USD ($) $ / shares in Units, $ in Millions

Aug. 07, 2017

Dec. 31, 2017

Sep. 30, 2017

Jun. 30, 2017

Mar. 31, 2017

Dec. 31, 2016

Sep. 30, 2016

Jun. 30, 2016

Mar. 31, 2016

Dec. 31, 2017

Dec. 31, 2016

Dec. 31, 2015

Class of Stock [Line Items]

Amortization of deferred launch incentives

$ 3

$ 13

$ 16

Series A, B and C Common Stock [Member]

Class of Stock [Line Items]

Basic (in dollars per share)

$ (1.99)

$ 0.38

$ 0.65

$ 0.37

$ 0.52

$ 0.37

$ 0.66

$ 0.42

$ (0.59)

$ 1.97

$ 1.59

Series C Convertible Preferred Stock [Member]

Class of Stock [Line Items]

Basic (in dollars per share)

38.07

30.74

Series C Convertible Preferred Stock [Member] | Advance Programming Holdings, LLC [Member]

Class of Stock [Line Items]

Common Stock, Conversion Basis

2

Series C-1 Preferred Stock [Member] [Domain]

Class of Stock [Line Items]

Basic (in dollars per share)

$ (11.33)

Series C-1 Preferred Stock [Member] [Domain] | Advance Programming Holdings, LLC [Member]

Class of Stock [Line Items]

Common Stock, Conversion Basis

19.3648

Scenario, Previously Reported [Member] | Series A, B and C Common Stock [Member]

Class of Stock [Line Items]

Basic (in dollars per share)

1.97

1.59

Scenario, Previously Reported [Member] | Series C Convertible Preferred Stock [Member]

Class of Stock [Line Items]

Basic (in dollars per share)

$ 3.94

$ 3.18

Summary Of Significant Accoun60

Summary Of Significant Accounting Policies - Additional Information (Details)	Nov. 30, 2016USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017USD ($)Customers	Dec. 31, 2016USD ($)Customers	Dec. 31, 2015USD ($)Customers
Summary Of Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification			$ 0
Deferred income taxes				$ 0
Impairment of goodwill	$ 0	$ 1,300,000,000	1,327,000,000	0	$ 0
Goodwill, Impairment Loss If New Guidance Early Adopted			100,000,000
Available-For-Sale Securities, Expected Amortization of Transition Asset (Obligation), Next Fiscal Year		26,000,000	26,000,000
Foreign currency transaction gain (loss), before tax			$ 83,000,000	(75,000,000)	103,000,000
Dividend yield			0.00%
Advertising expense			$ 162,000,000	$ 166,000,000	$ 148,000,000
Number of cable and satellite operators, US | Customers			10
Number of cable and satellite operators, Non-US | Customers			10
Concentration risk, number of customers | Customers			0	0	0
Deferred tax assets, net, noncurrent				$ 20,000,000
Deferred income taxes		(319,000,000)	$ (319,000,000)	(467,000,000)
Deferred Tax Liabilities, Net		(255,000,000)	$ (255,000,000)	$ (447,000,000)
Distribution Revenue [Member] | United States [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			90.00%
Distribution Revenue [Member] | Other Non United States [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			42.00%
Sales [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			10.00%	10.00%	10.00%
Minimum [Member] | Buildings [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			15 years
Minimum [Member] | Broadcast Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			3 years
Minimum [Member] | Capitalized Software [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			2 years
Minimum [Member] | Office Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			3 years
Minimum [Member] | Assets Held under Capital Leases [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			1 year
Minimum [Member] | Media Content [Member]
Summary Of Significant Accounting Policies [Line Items]
Content capitalization duration threshold			1 year
Content rights, useful life			3 years
Maximum [Member] | Buildings [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			39 years
Maximum [Member] | Broadcast Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			5 years
Maximum [Member] | Capitalized Software [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			5 years
Maximum [Member] | Office Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			5 years
Maximum [Member] | Assets Held under Capital Leases [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life			15 years
Maximum [Member] | Media Content [Member]
Summary Of Significant Accounting Policies [Line Items]
Content rights, useful life			4 years
Credit Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Derivative assets		$ 25,000,000	$ 25,000,000
FASB Guidance Reclassifying Debt Extinguishment Costs From Operating Activities To Financing Activities [Member]
Summary Of Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification					$ 5,000,000
Adjustments for New Accounting Pronouncement [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred income taxes				$ 97,000,000
Deferred tax assets, net, noncurrent				9,000,000
Deferred income taxes				(553,000,000)
Deferred Tax Liabilities, Net				$ (447,000,000)

Summary Of Significant Accoun61

Summary Of Significant Accounting Policies - Share-Based Payments (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncement, Early Adoption [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 0
Adjustments to APIC related to adoption of accounting pronouncements		$ 7	$ 12
Reductions to diluted earnings per share (in dollars per share)			$ 0.01
Cash flows from operating activities	1,629	1,380	$ 1,294
Cash used in financing activities	5,951	$ (1,184)	$ (919)
Retained Earnings [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ (4)

Summary Of Significant Accoun62

Summary Of Significant Accounting Policies - Balance Sheet Classification of Deferred Taxes (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncement, Early Adoption [Line Items]
Derivative Asset, Fair Value of Collateral	$ 3
Current deferred income tax assets		$ 0
Noncurrent deferred income tax assets (included within other noncurrent assets)		20
Noncurrent deferred income tax liabilities	(319)	(467)
Deferred Tax Liabilities, Net	$ (255)	$ (447)

Acquisitions And Dispositions63

Acquisitions And Dispositions (Narrative) (Details) $ / shares in Units, € in Millions	Nov. 30, 2017USD ($)	Sep. 25, 2017USD ($)	Apr. 28, 2017USD ($)	Dec. 02, 2016USD ($)	Oct. 07, 2015USD ($)	Oct. 01, 2015USD ($)	Oct. 01, 2015EUR (€)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Mar. 31, 2015EUR (€)	May 30, 2014USD ($)	Mar. 31, 2018USD ($)$ / sharesRateshares	Dec. 31, 2017USD ($)shares	Sep. 30, 2017USD ($)$ / shares	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2015EUR (€)	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Feb. 26, 2018USD ($)	Nov. 29, 2017	Jun. 30, 2017USD ($)$ / sharesshares	Apr. 01, 2016EUR (€)	Jun. 30, 2015EUR (€)	Dec. 31, 2014USD ($)	Dec. 21, 2012
Business Acquisition [Line Items]
Initial fair value of redeemable noncontrolling interests of acquired businesses														$ 82,000,000					$ 137,000,000	$ 0	$ 60,000,000
Reclassifications of Temporary to Permanent Equity														$ 38,000,000					38,000,000	0
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests													$ 413,000,000			$ 241,000,000			413,000,000	243,000,000	241,000,000						$ 747,000,000
Goodwill, Written off Related to Sale of Business Unit																			30,000,000	22,000,000
Remeasurement gain on previously held equity interests																			34,000,000	0	2,000,000
Purchase of redeemable noncontrolling interests																			0	0	548,000,000
Business Combination, Contingent Consideration, Liability													4,000,000			91,000,000			4,000,000		91,000,000
Goodwill													7,073,000,000			8,164,000,000			7,073,000,000	8,040,000,000	8,164,000,000
Intangible Assets, Net (Excluding Goodwill)													1,770,000,000						1,770,000,000	1,512,000,000
Gain (loss) on disposition																			4,000,000	(63,000,000)	17,000,000
Business Combination, Consideration Transferred, Other																			0	32,000,000	0
Proceeds from dispositions, net of cash disposed																			29,000,000	19,000,000	61,000,000
Property and equipment, net													597,000,000						597,000,000	482,000,000
SBS Radio [Member]
Business Acquisition [Line Items]
Gain (loss) on disposition								$ 1,000,000							$ (13,000,000)	12,000,000
Disposal Group, Including Discontinued Operation, Consideration								$ 80,000,000									$ 80,000,000									€ 72
Proceeds from dispositions, net of cash disposed																	$ 61,000,000	€ 54
Business disposal, contingent consideration, asset													$ 19,000,000						$ 19,000,000						€ 18
All3Media [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent													50.00%						50.00%
Raw Betty [Member]
Business Acquisition [Line Items]
Goodwill, Written off Related to Sale of Business Unit			$ 30,000,000
Gain (loss) on disposition																			$ (4,000,000)
Business Combination, Consideration Transferred, Other			$ 38,000,000
GroupNineMediaJV [Member]
Business Acquisition [Line Items]
Goodwill, Written off Related to Sale of Business Unit				$ 22,000,000
Business Combination, Consideration Transferred				$ 100,000,000
Noncontrolling Interest, Ownership Percentage by Parent				39.00%									42.00%						42.00%
Gain (loss) on disposition				$ (50,000,000)
Business Combination, Consideration Transferred, Other				$ 32,000,000
RussiaJV [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage					0.00%
Goodwill, Written off Related to Sale of Business Unit					$ 15,000,000
Gain (loss) on disposition					5,000,000
Investments in equity method investees, net					$ 0
Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares																								130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares														$ 23.86
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares																								3,000,000
Share Based Compensation, Converting to Cash																								$ 2,000,000
Business Acquisition, Share Price | $ / shares																								$ 50.34
Harpo [Member]
Business Acquisition [Line Items]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests													$ 55,000,000						$ 55,000,000
Cash consideration transferred	$ 70,000,000
Business Acquisition, Percentage of Voting Interests Acquired	73.99%																						49.50%
Remeasurement gain on previously held equity interests	$ 33,000,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets													707,000,000						707,000,000
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities													505,000,000						505,000,000
Goodwill	136,000,000
Intangible Assets	$ 295,000,000
VTEN [Member]
Business Acquisition [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity		67.50%
Weighted Average Amortization Period (Years)		16 years
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests													$ 120,000,000						$ 120,000,000
Goodwill		$ 75,000,000
Intangible Assets, Net (Excluding Goodwill)		53,000,000
Property and equipment, net		17,000,000
Other Assets		6,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		(7,000,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		144,000,000
Eurosport France [Member]
Business Acquisition [Line Items]
Initial fair value of redeemable noncontrolling interests of acquired businesses									$ 60,000,000
Equity Method Investment, Ownership Percentage																												20.00%
Increase or Decrease in ownership, percentage						49.00%	49.00%		31.00%	31.00%
Business Combination, Consideration Transferred									$ 38,000,000	€ 36
Business Acquisition, Percentage of Voting Interests Acquired									51.00%
Remeasurement gain on previously held equity interests									$ 2,000,000
Content rights, useful life									10 years	10 years
Goodwill									$ 69,000,000
Intangible Assets									$ 40,000,000
Eurosport [Member]
Business Acquisition [Line Items]
Increase or Decrease in ownership, percentage						49.00%	49.00%
Purchase of redeemable noncontrolling interests						$ 548,000,000	€ 491
Eurosport International [Member]
Business Acquisition [Line Items]
Initial fair value of redeemable noncontrolling interests of acquired businesses											$ 558,000,000
Content rights, useful life											10 years
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred																				$ 2,000,000
Business Combination, Contingent Consideration, Liability																$ 13,000,000					$ 13,000,000
Scenario, Previously Reported [Member] | VTEN [Member]
Business Acquisition [Line Items]
Goodwill		59,000,000
Intangible Assets, Net (Excluding Goodwill)		71,000,000
Property and equipment, net		16,000,000
Other Assets		6,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		(8,000,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		144,000,000
Scenario, Adjustment [Member] | VTEN [Member]
Business Acquisition [Line Items]
Goodwill		16,000,000
Intangible Assets, Net (Excluding Goodwill)		(18,000,000)
Property and equipment, net		1,000,000
Other Assets		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		1,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		$ 0
Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity												80.00%
Business Combination, Consideration Transferred												$ 11,968,000,000
Cash consideration transferred												8,400,000,000
Business Acquisition, Estimated Consideration to be Paid in Stock												3,600,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt												$ 2,700,000,000
Business Acquisition, Share Price Portion Paid in Cash | $ / shares												$ 63
Business Acquisition, Estimated Consideration to be Paid in Cash												$ 8,193,000,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												1.1316
Business combination, Post-acquisition ownership percentage of the Acquiree in the Combined Entity												20.00%
Business Acquisition, Share Price Portion Paid in Common Stock | $ / shares												$ 27
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares												147,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares												$ 1,000,000
Business Acquisition, Estimated Consideration to be Paid in Stock for Acquiree Shares Outstanding												$ 3,511,000,000
Business Acquisition, Share Price Portion of Stock Compensation Paid in Cash												$ 114,000,000
Stock Option Conversion Ratio | Rate												300.00%
business acquisition, number of share-based awards issued or issuable | shares												3,000,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable												$ 12.84
Business Acquisition, Share Price Portion of Stock Compensation Paid in Equity												45,000,000
Business Acquisition, Transaction Costs												$ 105,000,000
Subsequent Event [Member] | Scenario, Forecast [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												1.0584
Business Acquisition, Share Price Ceiling for Cash Settlement Option | $ / shares												$ 25.51
Minimum [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares													130,000,000						130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares																			$ 22.32
Minimum [Member] | Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred												$ 11,968,000,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												1.2096
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares												157,000,000
Minimum [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												0.9408
Business Acquisition, Share Price High End of Range | $ / shares												$ 28.70
Maximum [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares													130,000,000						130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares																			$ 28.70
Maximum [Member] | Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred												$ 11,968,000,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												0.9408
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares												122,000,000
Maximum [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares												1.2096
Business Acquisition, Acquiror Share Price, Low End of Range | $ / shares												$ 22.32
GoldenTree Asset Management L.P. [Member] | VTEN [Member]
Business Acquisition [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity		32.50%
Advance Programming Holdings, LLC [Member]
Business Acquisition [Line Items]
Preferred stock modification, change in fair value													$ 35,000,000
Education Business [Member] | Subsequent Event [Member]
Business Acquisition [Line Items]
Disposal Group, Including Discontinued Operation, Consideration																						$ 120,000,000

Acquisitions And Dispositions64

Acquisitions And Dispositions (Schedule of Purchase Price Allocation) (Details) $ / shares in Units, € in Millions	Nov. 30, 2017USD ($)	Mar. 31, 2015USD ($)	Mar. 31, 2015EUR (€)	Mar. 31, 2018USD ($)$ / sharesshares	Sep. 30, 2017$ / shares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jun. 30, 2017shares
Business Acquisition [Line Items]
Goodwill						$ 7,073,000,000	$ 8,040,000,000	$ 8,164,000,000
Remeasurement gain on previously held equity interests						(34,000,000)	0	$ (2,000,000)
Redeemable noncontrolling interests						$ (413,000,000)	$ (243,000,000)
Harpo [Member]
Business Acquisition [Line Items]
Goodwill	$ 136,000,000
Intangible Assets	295,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	176,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	84,000,000
Other assets acquired	26,000,000
Liabilities assumed	(230,000,000)
Remeasurement gain on previously held equity interests	(33,000,000)
Redeemable noncontrolling interests	(55,000,000)
Carrying value of previously held equity interest	(329,000,000)
Net assets acquired	351,000,000
Cash consideration transferred	$ 70,000,000
Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares									130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares					$ 23.86
Eurosport France [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 38,000,000	€ 36
Goodwill		69,000,000
Intangible Assets		40,000,000
Other assets acquired		25,000,000
Liabilities assumed		(30,000,000)
Cash		35,000,000
Removal of TF1 Put Right		2,000,000
Currency translation adjustment		(6,000,000)
Remeasurement gain on previously held equity interests		(2,000,000)
Deferred tax liabilities		(14,000,000)
Redeemable noncontrolling interests		(60,000,000)
Carrying value of previously held equity interest		(21,000,000)
Net assets acquired		$ 38,000,000
Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Share Price Portion Paid in Equity | $ / shares				$ 1,000,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares				1.1316
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares				147,000,000
Business Combination, Consideration Transferred				$ 11,968,000,000
Cash consideration transferred				$ 8,400,000,000
Minimum [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares						130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares						$ 22.32
Minimum [Member] | Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares				1.2096
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares				157,000,000
Business Combination, Consideration Transferred				$ 11,968,000,000
Maximum [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Shares, Outstanding | shares						130,000,000
Business Acquisition, Share Price Portion Paid in Equity | $ / shares						$ 28.70
Maximum [Member] | Subsequent Event [Member] | Scripps Networks Interactive [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares				0.9408
BusinessAcquisitionEquityInterestIssuedAssumedtobeIssued | shares				122,000,000
Business Combination, Consideration Transferred				$ 11,968,000,000

Investments (Narrative) (Detail

Investments (Narrative) (Details) € in Millions, shares in Millions	Dec. 02, 2016USD ($)	Nov. 12, 2015USD ($)shares	Oct. 01, 2015	Mar. 31, 2015USD ($)	Mar. 31, 2015EUR (€)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2017USD ($)	Dec. 21, 2012
Investments [Line Items]
Percentage Of Shares Pledged As Collateral						50.00%				50.00%
Senior Notes, Current						$ 6,800,000,000				$ 6,800,000,000
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Maximum Amount						$ 5,900,000,000				$ 5,900,000,000
Mandatory Redeemable Senior Notes, Percent						101.00%				101.00%
Other-than-temporary impairment of AFS investments						$ 0	$ 62,000,000	$ 0
Other Investments and Securities, at Cost						295,000,000	245,000,000		$ 245,000,000	$ 295,000,000
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount						204,000,000				204,000,000
Carrying value of investments in VIE's accounted for using the equity method						181,000,000	426,000,000		426,000,000	181,000,000
Income taxes						176,000,000	453,000,000	511,000,000
Variable Interest Entity Equity Gains (Losses)						(182,000,000)	7,000,000	30,000,000
Put Right Obligations							0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal						(4,000,000)	63,000,000	(17,000,000)
various equity method investments, aggregated [Member]
Investments [Line Items]
Investments in equity method investees, net						73,000,000
Lionsgate [Member]
Investments [Line Items]
Available-for-sale Securities, Noncurrent						164,000,000	128,000,000		128,000,000	164,000,000
Other-than-temporary impairment of AFS investments									62,000,000	62,000,000
Purchase of Available for Sale Securities, Shares | shares		5
Percentage ownership acquired of AFS security		3.00%
Available-for-sale Securities, Amortized Cost Basis		$ 195,000,000
Unrealized Gain (Loss) on Investments									14,000,000	32,000,000
Increase (Decrease) in Fair Value of Hedged Item in Price Risk Fair Value Hedge									(19,000,000)	(1,000,000)
GroupNineMediaJV [Member]
Investments [Line Items]
Business Combination, Consideration Transferred	$ 100,000,000
Other Investments and Securities, at Cost						$ 212,000,000	182,000,000		182,000,000	$ 212,000,000
Noncontrolling Interest, Ownership Percentage by Parent	39.00%					42.00%				42.00%
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ 50,000,000
Payments to Acquire Other Investments						$ 50,000,000	18,000,000
Eurosport [Member]
Investments [Line Items]
Increase or Decrease in ownership, percentage			49.00%
Eurosport France [Member]
Investments [Line Items]
Business Combination, Consideration Transferred				$ 38,000,000	€ 36
Equity Method Investment, Ownership Percentage											20.00%
Business Acquisition, Percentage of Voting Interests Acquired				51.00%	51.00%
Increase or Decrease in ownership, percentage			49.00%	31.00%	31.00%
Series of Individually Immaterial Business Acquisitions [Member]
Investments [Line Items]
Business Combination, Consideration Transferred							2,000,000
OWN Joint Venture [Member]
Investments [Line Items]
Advances to and note receivable from OWN						0	311,000,000		311,000,000	$ 0
Solar Ventures [Member]
Investments [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount						20,000,000				20,000,000
Carrying value of investments in VIE's accounted for using the equity method						98,000,000	39,000,000		39,000,000	98,000,000
Income taxes						294,000,000	26,000,000
Income (Loss) from Subsidiaries, Tax Expense (Benefit)						83,000,000	9,000,000
Income Tax Credits and Adjustments						211,000,000	17,000,000
Variable Interest Entity Equity Gains (Losses)						251,000,000	24,000,000
Investments in equity method investees, net						322,000,000	63,000,000
Equity Method Investments [Member]
Investments [Line Items]
Interest and Other Income						13,000,000	17,000,000	$ 23,000,000
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member]
Investments [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure						1,305,000,000				1,305,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member]
Investments [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure						1,305,000,000	$ 0		$ 0	1,305,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member]
Investments [Line Items]
Money Market Funds, at Carrying Value						2,700,000,000				2,700,000,000
CertificatesOfDepositRestrictedFairValueDisclosure						$ 0				$ 0

Investments (Schedule of Invest

Investments (Schedule of Investments) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Available-for-sale securities	$ 82,000,000	$ 64,000,000
Available-for-sale Securities Pledged as Collateral	82,000,000	64,000,000
Trading Securities		160,000,000
Equity method investments, including note receivable	335,000,000	557,000,000
Cost Method Investments	4,988,000,000	1,090,000,000
Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	1,305,000,000
Trading Securities	2,707,000,000
Other Current Assets [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
Trading Securities	182,000,000
Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	1,305,000,000	0
Trading Securities	0
Fair Value, Inputs, Level 2 [Member] | Other Current Assets [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
Trading Securities	0	0
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	0
Trading Securities	2,707,000,000	0
Fair Value, Inputs, Level 1 [Member] | Other Current Assets [Member] | Fair Value, Measurements, Recurring [Member]
Investment [Line Items]
Trading Securities	182,000,000	160,000,000
Money Market Funds [Member]
Investment [Line Items]
Available-for-sale securities	295,000,000	245,000,000
OWN Note Receivable [Member]
Investment [Line Items]
Equity method investments, including note receivable	0	311,000,000
Equity Method Investments [Member]
Investment [Line Items]
Equity method investments, including note receivable	$ 335,000,000	$ 246,000,000

Investments (Schedule of Equity

Investments (Schedule of Equity Method Investments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selected Statement of Operations Information:
Revenues	$ 1,780	$ 1,617	$ 1,324
Cost of sales	1,100	998	853
Operating income	76	83	42
Pre-tax income (loss) from continuing operations before extraordinary items	16	(78)	(42)
After-tax net loss	(27)	(98)	(42)
Net loss attributable to the entity	(27)	(99)	$ (42)
Selected Balance Sheet Information:
Current assets	1,002	884
Noncurrent assets	1,946	1,646
Current liabilities	701	752
Noncurrent liabilities	1,008	1,177
Redeemable preferred stock	476	0
Non-controlling interests	$ 6	$ 8

Investments (Schedule of Availa

Investments (Schedule of Available for Sale Investments) (Details) - USD ($) $ in Millions	12 Months Ended			14 Months Ended	26 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2017	Nov. 12, 2015
Schedule of Available-for-sale Securities [Line Items]
Other-than-temporary impairment of AFS investments	$ 0	$ 62	$ 0
Lionsgate [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis						$ 195
Unrealized Gain (Loss) on Investments				$ 14	$ 32
Available-for-sale Securities, Noncurrent	$ 164	$ 128		128	164
Other-than-temporary impairment of AFS investments				62	62
Increase (Decrease) in Fair Value of Hedged Item in Price Risk Fair Value Hedge				$ (19)	$ (1)

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Billions	Dec. 31, 2017	Dec. 31, 2016
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes, fair value	$ 14.8	$ 7.4

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Assets And Liabilities Measured On Recurring Basis) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds		$ 160,000,000
Available-for-sale securities	$ 82,000,000	64,000,000
Available-for-sale Securities Pledged as Collateral	82,000,000	64,000,000
Total assets	4,383,000,000	380,000,000
Deferred compensation plan	182,000,000	160,000,000
Total liabilities	320,000,000	212,000,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	3,053,000,000	288,000,000
Total liabilities	182,000,000	160,000,000
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	1,330,000,000	92,000,000
Total liabilities	138,000,000	52,000,000
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	0	0
Total liabilities	0	0
Prepaid expenses and other current assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds		160,000,000
Derivative assets		31,000,000
Other Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		25,000,000
Other Noncurrent Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	82,000,000
Available-for-sale Securities Pledged as Collateral	82,000,000
Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	12,000,000	18,000,000
Accrued Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	33,000,000	21,000,000
Other Noncurrent Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	105,000,000	31,000,000
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	1,305,000,000
Trading securities - mutual funds	2,707,000,000
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	0
Trading securities - mutual funds	2,707,000,000	0
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	1,305,000,000	0
Trading securities - mutual funds	0
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
CertificatesOfDepositRestrictedFairValueDisclosure	0
Trading securities - mutual funds	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	82,000,000	64,000,000
Available-for-sale Securities Pledged as Collateral	82,000,000	64,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	0	0
Available-for-sale Securities Pledged as Collateral	0	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	0	0
Available-for-sale Securities Pledged as Collateral	0	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		1,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		1,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		0
Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	182,000,000	160,000,000
Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	0	0
Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	0	0
Fair Value, Measurements, Recurring [Member] | Other Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities		64,000,000
Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds	182,000,000
Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds	182,000,000	160,000,000
Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds	0	0
Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities - mutual funds	0	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Credit Risk Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	1,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Credit Risk Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Credit Risk Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	1,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Credit Risk Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	6,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	0
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	6,000,000
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liabilities	0
Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	13,000,000
Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	98,000,000
Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0
Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	12,000,000	18,000,000
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		31,000,000
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	12,000,000	18,000,000
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	7,000,000
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	7,000,000
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	8,000,000	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	13,000,000	3,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	98,000,000	31,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	3,000,000	35,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	3,000,000	35,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	8,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	8,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability		3,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Currency Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	13,000,000	3,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Accrued Liabilities [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	2,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	2,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Prepaid expenses and other current assets [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability		31,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability		0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	98,000,000	31,000,000
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Liabilities [Member] | Currency Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability		0
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Equity Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Equity Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Hedging [Member] | Lionsgate [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Equity Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	13,000,000
Fair Value Hedging [Member] | Lionsgate [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Equity Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Fair Value Hedging [Member] | Lionsgate [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Equity Contract [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	13,000,000	25,000,000
Fair Value Hedging [Member] | Lionsgate [Member] | Designated as Hedging Instrument [Member] | Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member] | Equity Contract [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	$ 0	$ 0

Content Rights (Narrative) (Det

Content Rights (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Percentage of unamortized content rights	96.00%
Years from date of balance sheet	P3Y
Amortization of unamortized content rights	$ 1,100

Content Rights (Schedule Of Con

Content Rights (Schedule Of Content Rights) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Licensed content rights:
Content rights, at cost	$ 2,638	$ 2,141
Accumulated amortization	(4,197)	(3,849)
Total content rights, net	2,623	2,399
Current portion	(410)	(310)
Noncurrent portion	2,213	2,089
Media Content [Member]
Produced content rights:
Completed	4,355	3,920
In-production	442	420
Coproduced content rights:
Completed	745	632
In-production	27	57
Licensed content rights:
Acquired	1,070	1,090
Prepaid	181	129
Content rights, at cost	6,820	$ 6,248
Olympic [Member]
Licensed content rights:
Prepaid	$ 83

Content Rights Content Rights (

Content Rights Content Rights (Schedule of Content Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
ContentImpairmentsInRestructuringAndOtherCharges	$ 7	$ 3	$ 21
Content amortization	1,878	1,701	1,628
Other production charges	310	272	81
Content impairments	32	72	231	[1]
Total content expense	2,220	2,045	1,940
Other Restructuring [Member]
ContentImpairmentsInRestructuringAndOtherCharges	$ 0	$ 7	$ 21
[1]	(a) Content impairments are generally recorded as a component of costs of revenue. However during the years ended December 31, 2016 and 2015, content impairments of $7 million and $21 million, respectively, were reflected as a component of restructuring and other charges. These impairment charges resulted from the cancellation of certain series due to legal circumstances pertaining to the associated talent. No content impairments were recorded as a component of restructuring and other during the year ended December 31, 2017.

Property And Equipment (Narrati

Property And Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property and Equipment [Line Items]
Capital leased assets, gross	$ 358	$ 284
Capital Lease, Accumulated Amortization	154	155
Capitalized software costs, net	86	96
Depreciation expense	330	322	$ 330
Rental expense for operating leases	127	122	134
Property and Equipment [Member]
Property and Equipment [Line Items]
Depreciation expense	$ 150	$ 139	$ 138

Property And Equipment (Compone

Property And Equipment (Components Of Property And Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Land, buildings and leasehold improvements	$ 363	$ 327
Broadcast equipment	728	607
Capitalized software costs	379	347
Office equipment, furniture, fixtures and other	431	333
Property and equipment, at cost	1,901	1,614
Accumulated depreciation	(1,304)	(1,132)
Property and equipment, net	$ 597	$ 482

Goodwill And Intangible Asset76

Goodwill And Intangible Assets (Narrative) (Details)	Nov. 30, 2017USD ($)	Nov. 30, 2016USD ($)	Dec. 31, 2017USD ($)renewal	Dec. 31, 2017USD ($)renewal	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Amortization expense, excluding impairment charges, related to finite-lived intangible assets				$ 180,000,000	$ 183,000,000	$ 192,000,000
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount					40.00%
Assets, Fair Value Disclosure			$ 4,383,000,000	4,383,000,000	$ 380,000,000
Impairment of goodwill		$ 0	1,300,000,000	1,327,000,000	0	0
Goodwill			7,073,000,000	7,073,000,000	8,040,000,000	8,164,000,000
International Networks [Member]
Accumulated impairments			1,300,000,000	1,300,000,000
Impairment of goodwill				1,327,000,000
Goodwill			1,555,000,000	1,555,000,000	2,708,000,000	2,800,000,000
U.S. Networks [Member]
Accumulated impairments					20,000,000	20,000,000
Impairment of goodwill				0
Goodwill			5,478,000,000	5,478,000,000	$ 5,265,000,000	$ 5,287,000,000
European Union [Member]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount	3.00%				12.00%
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount	$ 100,000,000		1,200,000,000	1,200,000,000
Assets, Fair Value Disclosure			3,900,000,000	3,900,000,000
Impairment of goodwill	1,300,000,000
Net Assets	4,000,000,000		2,700,000,000	2,700,000,000
Goodwill	2,400,000,000		$ 1,100,000,000	$ 1,100,000,000
Goodwill, Fair Value Disclosure	$ 3,900,000,000
Fair Value Inputs, Long-term Revenue Growth Rate				2.50%	3.00%
Fair Value Inputs, Discount Rate				9.75%	10.50%
Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple				7.5	9.5
Fair Value Inputs, Attrition Rate				10.00%
Number Of Contract Renewals | renewal			3	3
Contract Renewals, Term				4 years
Cash Flow Approach Valuation Technique [Member] | European Union [Member]
Goodwill Weighted Valuation, Percentage	75.00%
Market Approach Valuation Technique [Member] | European Union [Member]
Goodwill Weighted Valuation, Percentage	25.00%
Minimum [Member] | European Union [Member]
Fair Value Inputs, Royalty Rate				2.00%
Maximum [Member] | European Union [Member]
Fair Value Inputs, Royalty Rate				5.00%

Goodwill And Intangible Asset77

Goodwill And Intangible Assets (Goodwill By Reportable Segment) (Details) - USD ($)	Nov. 30, 2016	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill, Beginning Balance			$ 8,040,000,000	$ 8,164,000,000
Acquisitions			218,000,000
Dispositions			(30,000,000)	(22,000,000)
Foreign currency translation			172,000,000	(102,000,000)
Goodwill, Ending Balance		$ 7,073,000,000	7,073,000,000	8,040,000,000	$ 8,164,000,000
Impairment of goodwill	$ 0	(1,300,000,000)	(1,327,000,000)	0	0
U.S. Networks [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance			5,265,000,000	5,287,000,000
Acquisitions			211,000,000
Dispositions			0	(22,000,000)
Foreign currency translation			2,000,000	0
Goodwill, Ending Balance		5,478,000,000	5,478,000,000	5,265,000,000	5,287,000,000
Impairment of goodwill			0
International Networks [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance			2,708,000,000	2,800,000,000
Acquisitions			7,000,000
Dispositions			0	0
Foreign currency translation			167,000,000	(92,000,000)
Goodwill, Ending Balance		1,555,000,000	1,555,000,000	2,708,000,000	2,800,000,000
Impairment of goodwill			(1,327,000,000)
Education [Member]
Goodwill [Line Items]
Impairment of goodwill			0
Education And Other [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance			67,000,000	77,000,000
Acquisitions			0
Dispositions			30,000,000	0
Foreign currency translation			3,000,000	(10,000,000)
Goodwill, Ending Balance		$ 40,000,000	$ 40,000,000	$ 67,000,000	$ 77,000,000

Goodwill And Intangible Asset78

Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 2,638	$ 2,141
Accumulated Amortization	(1,032)	(793)
Finite-lived intangible assets net	$ 1,606	1,348
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	10 years
Finite-Lived Intangible Assets, Gross	$ 494	412
Accumulated Amortization	(224)	(165)
Finite-lived intangible assets net	$ 270	247
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	16 years
Finite-Lived Intangible Assets, Gross	$ 2,026	1,632
Accumulated Amortization	(758)	(594)
Finite-lived intangible assets net	$ 1,268	1,038
Others [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	16 years
Finite-Lived Intangible Assets, Gross	$ 118	97
Accumulated Amortization	(50)	(34)
Finite-lived intangible assets net	$ 68	$ 63

Goodwill And Intangible Asset79

Goodwill And Intangible Assets (Schedule Of Intangible Assets Not Subject To Amortization) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets by Major Class [Line Items]
Indefinite-lived intangible assets net (Trademarks)	$ 164	$ 164

Goodwill And Intangible Asset80

Goodwill And Intangible Assets (Amortization Expense For Intangible Assets) (Details) $ in Millions	Dec. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,015	$ 220
2,017	203
2,018	198
2,019	174
2,020	147
Thereafter	$ 664

Debt (Narrative) (Details)

Debt (Narrative) (Details) £ in Millions	Aug. 11, 2017USD ($)renewalRate	Mar. 13, 2017USD ($)	Sep. 30, 2017	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 21, 2017USD ($)	Sep. 21, 2017GBP (£)	Jul. 30, 2017USD ($)	Mar. 31, 2017	Mar. 31, 2016USD ($)	Mar. 02, 2015USD ($)
Debt Instrument [Line Items]
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Maximum Amount					$ 5,900,000,000
Long-term Debt, Gross					$ 14,913,000,000	$ 7,990,000,000
Effect of Exchange Rate on Cash				$ 1.35
Debt Instrument, Redemption Price, Percentage					101.00%
Payments of Debt Issuance Costs					$ 1,000,000
Line of Credit Facility, Amount Outstanding					425,000,000	550,000,000
Long-Term Line Of Credit Denominated In Foreign Currency					$ 0	207,000,000
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]					The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 )
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage					0.20%
Borrowings under revolving credit facility					$ 350,000,000	613,000,000	$ 1,016,000,000
Commercial Paper					0	48,000,000
Loss on extinguishment of debt					(54,000,000)	0	$ 0
Payment for Debt Extinguishment or Debt Prepayment Cost					50,000,000
Write off of Deferred Debt Issuance Cost					2,000,000
Repayments of Debt					1,000,000
Unsecured Long-term Debt, Noncurrent	$ 1,000,000,000
Debt Instrument, Fee			20
TWO POINT TWO ZERO ZERO SENIOR NOTES [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 500,000,000	0		$ 500,000,000
Debt instrument interest rate					0.00%			2.20%	2.20%
Debt Instrument, Maturity Date					Sep. 1, 2019
1.90% Euro Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 717,000,000	627,000,000
Debt instrument interest rate					1.90%
Debt Instrument, Maturity Date					Mar. 19, 2027
3.45% Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 300,000,000	300,000,000							$ 300,000,000
Debt instrument interest rate					3.45%		3.45%
Debt Instrument, Maturity Date					Mar. 15, 2025
2.375% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 358,000,000	314,000,000
Debt instrument interest rate					2.375%
Debt Instrument, Maturity Date					Mar. 7, 2022
4.90 Senior Notes [Member] [Domain] [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 200,000,000			$ 700,000,000	500,000,000
Debt instrument interest rate		4.90%			4.90%
Debt Instrument, Maturity Date					Mar. 11, 2026
Payments of Debt Issuance Costs		$ 2,000,000
Debt Instrument, Unamortized Premium		10,000,000
Three Point Eight Percent Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 450,000,000			$ 450,000,000	0
Debt instrument interest rate		3.80%			3.80%
Debt Instrument, Maturity Date					Mar. 1, 2024
Payments of Debt Issuance Costs		$ 4,000,000
Debt instrument total discount		1,000,000
Bridge Term Loan [Member]
Debt Instrument [Line Items]
Bridge Loan										$ 9,600,000,000
Payments of Debt Issuance Costs		40,000,000
Two Point Nine Five Senior Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 1,200,000,000	0		$ 1,200,000,000
Debt instrument interest rate					0.00%			2.95%	2.95%
Debt Instrument, Maturity Date					Mar. 1, 2023
Three Point Nine Five Senior Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 1,700,000,000	0		$ 1,700,000,000
Debt instrument interest rate					3.95%			3.95%	3.95%
Debt Instrument, Maturity Date					Mar. 1, 2028
Five Point Zero [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 1,250,000,000	0		$ 1,250,000,000
Debt instrument interest rate					5.00%			5.00%	5.00%
Debt Instrument, Maturity Date					Sep. 1, 2037
Five Point Two Senior Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 1,250,000,000	0		$ 1,250,000,000
Debt instrument interest rate					0.00%			5.20%	5.20%
Debt Instrument, Maturity Date					Sep. 1, 2047
Floating Rate Senior Notes [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 400,000,000	0		$ 400,000,000
Debt Instrument, Maturity Date					Sep. 1, 2019
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate					0.00%
5.05% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 600,000,000			$ 789,000,000	1,300,000,000
Debt instrument interest rate					5.05%						5.05%
Debt Instrument, Maturity Date					Jun. 1, 2020
Five Point Six Two Five Percent Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 411,000,000	500,000,000
Debt instrument interest rate					5.625%						5.625%
Debt Instrument, Maturity Date					Aug. 15, 2019
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 2,500,000,000	$ 2,000,000,000
Line Of Credit Facility, Number Of Renewal Periods | renewal	2
Line Of Credit Facility, Term Of Renewal Period	364 days
Debt, Weighted Average Interest Rate					2.69%	2.05%
Revolver sublimit for standby letters of credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity												$ 100,000,000
Revolver sublimit for swing line loans [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity												$ 50,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate					0.00%	1.20%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate					1.30%
Base Rate [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate					0.30%
Discovery Family [Member]
Debt Instrument [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					40.00%
Discovery Japan [Member]
Debt Instrument [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					20.00%
Sterling Notes [Member] | Two Point Five Senior Notes [Domain] [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross								$ 540,000,000	£ 400
Debt instrument interest rate								2.50%	2.50%
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net								$ 11,000,000
Debt Issuance Costs, Net								$ 57,000,000
Secured Debt [Member] | Three Year Delayed Draw Tranche Unsecured Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	3 years
Secured Debt [Member] | Five Year Delayed Draw Tranche Unsecured Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	5 years
Maximum [Member]
Debt Instrument [Line Items]
Supplementary Leverage Ratio | Rate	550.00%
Minimum [Member]
Debt Instrument [Line Items]
Supplementary Leverage Ratio | Rate	100.00%
Step Down 1 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Supplementary Leverage Ratio | Rate	500.00%
Step Down 1 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Supplementary Leverage Ratio | Rate	100.00%
Step Down 2 [Member] [Member] | Maximum [Member]
Debt Instrument [Line Items]
Supplementary Leverage Ratio | Rate	450.00%

Debt (Outstanding Debt) (Detail

Debt (Outstanding Debt) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Sep. 21, 2017	Mar. 31, 2017	Mar. 13, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 02, 2015
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ 425				$ 550
Commercial Paper	0				48
Capital Lease Obligations	225				151
Total debt	14,913				7,990
Unamortized discount	(128)				(67)
Debt, net	14,785				7,923
Current portion of debt	(30)				(82)
Noncurrent portion of debt	$ 14,755				7,841
5.625% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.625%		5.625%
Total debt	$ 411				500
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Aug. 15, 2019
5.05% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.05%		5.05%
Total debt	$ 789			$ 600	1,300
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 1, 2020
4.375% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.375%
Total debt	$ 650				650
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 15, 2021
2.375% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	2.375%
Total debt	$ 358				314
Long-term debt, frequency of periodic payments	annual
Debt Instrument, Maturity Date	Mar. 7, 2022
3.30% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.30%
Total debt	$ 500				500
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	May 15, 2022
3.25% Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.25%
Total debt	$ 350				350
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Apr. 1, 2023
3.45% Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	3.45%					3.45%
Total debt	$ 300				300		$ 300
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 15, 2025
4.90 Senior Notes [Member] [Domain] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	4.90%			4.90%
Total debt	$ 700			$ 200	500
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 11, 2026
1.90% Euro Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	1.90%
Total debt	$ 717				627
Long-term debt, frequency of periodic payments	annual
Debt Instrument, Maturity Date	Mar. 19, 2027
6.35% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	6.35%
Total debt	$ 850				850
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 1, 2040
4.95% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.95%
Total debt	$ 500				500
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	May 15, 2042
4.875% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.875%
Total debt	$ 850				850
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Apr. 1, 2043
TWO POINT TWO ZERO ZERO SENIOR NOTES [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	0.00%	2.20%
Total debt	$ 500	$ 500			0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Sep. 1, 2019
Floating Rate Senior Notes [Domain]
Debt Instrument [Line Items]
Total debt	$ 400	$ 400			0
Long-term debt, frequency of periodic payments	quarterly
Debt Instrument, Maturity Date	Sep. 1, 2019
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	0.00%
Two Point Nine Five Senior Notes [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	0.00%	2.95%
Total debt	$ 1,200	$ 1,200			0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 1, 2023
Three Point Eight Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.80%			3.80%
Total debt	$ 450			$ 450	0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 1, 2024
Two Point Five Senior Notes [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	0.00%
Total debt	$ 538				0
Long-term debt, frequency of periodic payments	annual
Debt Instrument, Maturity Date	Sep. 1, 2024
Three Point Nine Five Senior Notes [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	3.95%	3.95%
Total debt	$ 1,700	$ 1,700			0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 1, 2028
Five Point Zero [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	5.00%	5.00%
Total debt	$ 1,250	$ 1,250			0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Sep. 1, 2037
Five Point Two Senior Notes [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	0.00%	5.20%
Total debt	$ 1,250	$ 1,250			$ 0
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Sep. 1, 2047

Debt (Outstanding Debt, Additio

Debt (Outstanding Debt, Additional Information) (Details)	12 Months Ended
	Dec. 31, 2017	Mar. 31, 2017	Mar. 13, 2017	Dec. 31, 2015
4.90 Senior Notes [Member] [Domain] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	4.90%		4.90%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 11, 2026
5.625% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.625%	5.625%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Aug. 15, 2019
5.05% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.05%	5.05%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 1, 2020
4.375% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.375%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 15, 2021
2.375% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	2.375%
Long-term debt, frequency of periodic payments	annual
Debt Instrument, Maturity Date	Mar. 7, 2022
3.25% Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.25%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Apr. 1, 2023
3.45% Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	3.45%			3.45%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Mar. 15, 2025
1.90% Euro Senior Notes [Member] [Domain]
Debt Instrument [Line Items]
Debt instrument interest rate	1.90%
Long-term debt, frequency of periodic payments	annual
Debt Instrument, Maturity Date	Mar. 19, 2027
6.35% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	6.35%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Jun. 1, 2040
3.30% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.30%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	May 15, 2022
4.95% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.95%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	May 15, 2042
4.875% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.875%
Long-term debt, frequency of periodic payments	semi-annual
Debt Instrument, Maturity Date	Apr. 1, 2043

Debt (Schedule Of Debt Payments

Debt (Schedule Of Debt Payments) (Details) $ in Millions	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
2,018	$ 0
2,019	1,311
2,020	789
2,021	650
2,022	858
Thereafter	$ 10,655

Derivative Financial Instrume85

Derivative Financial Instruments (Narrative) (Details) £ in Millions

1 Months Ended

3 Months Ended

12 Months Ended

120 Months Ended

Oct. 31, 2016USD ($)

Mar. 31, 2015USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2016USD ($)

Dec. 31, 2015USD ($)

Mar. 31, 2025USD ($)

Sep. 30, 2017USD ($)

Sep. 21, 2017USD ($)

Sep. 21, 2017GBP (£)

Nov. 10, 2016USD ($)

Mar. 02, 2015USD ($)

Feb. 27, 2015USD ($)

Derivative [Line Items]

Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months

$ 6,000,000

Long-term Debt, Gross

14,913,000,000

$ 7,990,000,000

Derivative Asset, Fair Value, Amount Offset Against Collateral

$ 0

0

Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]

The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 )

Gain (Loss) on Fair Value Hedge Ineffectiveness, Net

$ (1,000,000)

(1,000,000)

Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net

(105,000,000)

(1,000,000)

$ 6,000,000

Interest Rate Contract [Member]

Derivative [Line Items]

Derivative Instruments Not Designated as Hedging Instruments, Gain

$ 1,000,000

AOCI Including Portion Attributable to Noncontrolling Interest, before Tax

$ (40,000,000)

$ 40,000,000

Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net

$ 11,000,000

Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net

(98,000,000)

0

0

Foreign Exchange Contract [Member]

Derivative [Line Items]

Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net

0

(1,000,000)

6,000,000

Foreign Exchange Forward and Forward Exchange Option [Member]

Derivative [Line Items]

Derivative, Notional Amount

125,000,000

Derivative Asset, Fair Value, Gross Asset

14,000,000

Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]

Derivative [Line Items]

Derivative, Notional Amount

25,000,000

25,000,000

Not Designated as Hedging Instrument [Member] | Currency Swap [Member]

Derivative [Line Items]

Derivative, Notional Amount

64,000,000

64,000,000

Accrued Liabilities [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]

Derivative [Line Items]

Derivative, Notional Amount

$ 490,000,000

Interest Expense [Member] | Interest Rate Contract [Member]

Derivative [Line Items]

Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net

1,000,000

3,000,000

$ 3,000,000

Scenario, Forecast [Member] | Interest Expense [Member] | Interest Rate Contract [Member]

Derivative [Line Items]

Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net

$ 29,000,000

Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Equity Contract [Member]

Derivative [Line Items]

Derivative, Notional Amount

97,000,000

97,000,000

3.45% Senior Notes [Member] [Domain]

Derivative [Line Items]

Long-term Debt, Gross

$ 300,000,000

$ 300,000,000

$ 300,000,000

Debt instrument interest rate

3.45%

3.45%

Scripps Networks Interactive [Member] | Interest Rate Contract [Member]

Derivative [Line Items]

Derivative, Notional Amount

$ 4,000,000,000

Sterling Notes [Member] | Two Point Five Senior Notes [Domain] [Domain]

Derivative [Line Items]

Long-term Debt, Gross

$ 540,000,000

£ 400

Debt instrument interest rate

2.50%

2.50%

Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net

$ (12,000,000)

Derivative Financial Instrume86

Derivative Financial Instruments (Schedule of Derivative Instruments, Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Feb. 27, 2015
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 9	$ 31
Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	16	61
Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	33	21
Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	105	31
Currency Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	64	64
Currency Swap [Member] | Not Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Currency Swap [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	1
Currency Swap [Member] | Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Currency Swap [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	6	0
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount			$ 490
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	25	25
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Credit Risk Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	665	0
Credit Risk Contract [Member] | Not Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Credit Risk Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Credit Risk Contract [Member] | Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Credit Risk Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	1	0
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	817	677
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	7	31
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	12	18
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	303	0
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2	0
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	8	0
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Net Investment Hedging [Member] | Currency Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,708	751
Net Investment Hedging [Member] | Currency Swap [Member] | Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Net Investment Hedging [Member] | Currency Swap [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	3	35
Net Investment Hedging [Member] | Currency Swap [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	13	3
Net Investment Hedging [Member] | Currency Swap [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	98	31
Fair Value Hedging [Member] | Equity Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	97	97
Fair Value Hedging [Member] | Equity Contract [Member] | Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Fair Value Hedging [Member] | Equity Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	13	25
Fair Value Hedging [Member] | Equity Contract [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Hedging [Member] | Equity Contract [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0	$ 0

Derivative Financial Instrume87

Derivative Financial Instruments (Schedule of Comprehensive Income Impact of Items Designated as Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ (41)	$ (1)	$ 34
Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	0	40	(11)
Distribution Revenue [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(22)	(25)	23
Advertising Revenue [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(3)	(2)	2
Cost of Sales [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	27	9
Other Expense [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	3	4
Derivative, Net Hedge Ineffectiveness Gain (Loss)	0	1	0
Gain (Loss) from Components Excluded from Assessment of Cash Flow Hedge Effectiveness, Net	0	(5)	0
Other Expense [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Net Hedge Ineffectiveness Gain (Loss)	17	0	(11)
Interest Expense [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (1)	$ (3)	$ (3)

Derivative Financial Instrume88

Derivative Financial Instruments Schedule of Comprehensive Income Impact of Items Designated as Net Investment Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Currency Swap [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ (109)	$ 1	$ 0
Interest Paid, Net	(13)	(2)	0
Derivatives used in Net Investment Hedge, Increase (Decrease), Gross of Tax	(112)	3	0
Foreign Exchange [Member]
Derivative [Line Items]
Change in Unrealized Gain (Loss) on Foreign Currency Fair Value Hedging Instruments	(18)	0	0
Sterling Notes [Member] | Foreign Exchange [Member]
Derivative [Line Items]
Change in Unrealized Gain (Loss) on Foreign Currency Fair Value Hedging Instruments	$ 2	$ 0	$ 0

Derivative Financial Instrume89

Derivative Financial Instruments (Schedule of Pre-Tax Gains (Losses) of Items Designated as Fair Value Hedges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	$ 1	$ 1
Equity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	18	(17)	$ (2)
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(17)	16	2
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net	5	(6)	10
Equity Contract [Member] | Other Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	$ 6	$ (7)	$ 10

Derivative Financial Instrume90

Derivative Financial Instruments (Schedule of Pre-Tax Gains (Losses) of Items Not Designated as Hedges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (105)	$ (1)	$ 6
Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(98)	0	0
Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(6)	0	0
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	0	(1)	6
Credit Risk Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (1)	$ 0	$ 0

Redeemable Noncontrolling Int91

Redeemable Noncontrolling Interest (Narrative) (Details) € in Millions, $ in Millions	Oct. 01, 2015USD ($)	Oct. 01, 2015EUR (€)	Mar. 31, 2015USD ($)	May 30, 2014USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Sep. 30, 2017USD ($)	Sep. 30, 2015USD ($)	Dec. 31, 2022	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Nov. 30, 2017USD ($)	Nov. 29, 2017	Sep. 25, 2017	Jul. 22, 2015EUR (€)	Dec. 31, 2014USD ($)
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests					$ 413					$ 413	$ 243
Initial fair value of redeemable noncontrolling interests of acquired businesses							$ 82			137	0	$ 60
Reclassifications of Temporary to Permanent Equity							$ 38			38	0
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					413					413	243	241					$ 747
Purchase of redeemable noncontrolling interests										0	0	548
Purchase of redeemable noncontrolling interest											(1)	0
RedeemableNoncontrollingInterestDecreaseFromRedemptions								$ 551		$ 0	0	551
Adjustments of redemption values to the floor												73
Terms Of Put Arrangement										1 year
Additional Paid-In Capital [Member]
Redeemable Noncontrolling Interest [Line Items]
Purchase of redeemable noncontrolling interest	$ 61										0	61
Accumulated Other Comprehensive (Loss)/Income [Member]
Redeemable Noncontrolling Interest [Line Items]
Purchase of redeemable noncontrolling interest											$ 0	$ (61)
Harpo [Member]
Redeemable Noncontrolling Interest [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired													73.99%	49.50%
Redeemable noncontrolling interests													$ 55
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					55					$ 55
VTEN [Member]
Redeemable Noncontrolling Interest [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity															67.50%
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					$ 120					$ 120
Eurosport France [Member]
Redeemable Noncontrolling Interest [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired			51.00%
Redeemable noncontrolling interests			$ 60
Initial fair value of redeemable noncontrolling interests of acquired businesses			$ 60
Increase or Decrease in ownership, percentage	49.00%	49.00%	31.00%
Discovery Family [Member]
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					40.00%					40.00%
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					$ 210					$ 210
Eurosport International [Member]
Redeemable Noncontrolling Interest [Line Items]
Initial fair value of redeemable noncontrolling interests of acquired businesses				$ 558
Eurosport [Member]
Redeemable Noncontrolling Interest [Line Items]
Increase or Decrease in ownership, percentage	49.00%	49.00%
Purchase of redeemable noncontrolling interests	$ 548	€ 491
MandatorilyRedeemableNoncontrollinginterestreclassifiedtocurrentliabilities | €																€ 491
Adjustments of redemption values to the floor					$ 28	€ 25
Discovery Japan [Member]
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					20.00%					20.00%
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					$ 27					$ 27
Scenario, Forecast [Member] | Discovery Family [Member]
Redeemable Noncontrolling Interest [Line Items]
Terms Of Put Arrangement									1 year
GoldenTree Asset Management L.P. [Member] | VTEN [Member]
Redeemable Noncontrolling Interest [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity															32.50%

Redeemable Noncontrolling Int92

Redeemable Noncontrolling Interest (Schedule of Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Increase (Decrease) In Redeemable Noncontrolling Interest [Roll Forward]
Beginning Balance		$ 747	$ 243	$ 241	$ 747
Initial fair value of redeemable noncontrolling interests of acquired businesses	$ 82		137	0	60
Purchase of subsidiary shares at fair value		$ (551)	0	0	(551)
Cash distributions to redeemable noncontrolling interests			(30)	(22)	(42)
Net income attributable to redeemable noncontrolling interests			24	23	13
Other comprehensive loss attributable to redeemable noncontrolling interests			1	0	(23)
Currency translation on redemption values			0	1	(36)
Adjustments of redemption values to the floor					73
Ending Balance			$ 413	$ 243	$ 241

Equity (Narrative) (Details)

Equity (Narrative) (Details)	Mar. 15, 2017USD ($)	Dec. 02, 2016USD ($)shares	Mar. 31, 2018shares	Dec. 31, 2017USD ($)$ / sharesshares	Sep. 30, 2017USD ($)shares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2017USD ($)shares$ / shares	Dec. 31, 2016USD ($)shares	Dec. 31, 2015USD ($)shares	Aug. 07, 2017USD ($)shares	Jun. 30, 2017USD ($)	Dec. 15, 2016USD ($)	Aug. 22, 2016USD ($)	Sep. 17, 2008shares
preferred stock convertible amount fair value | $					$ 3,375,000,000					$ 3,340,000,000
Voting and purchase rights subject to agreement between Dr. Malone and David Zaslav				6,000,000			6,000,000
Treasury Stock, Value | $				$ 6,737,000,000		$ 6,356,000,000	$ 6,737,000,000	$ 6,356,000,000
Share Conversion (in shares)								(1,000,000)
Additional Paid in Capital | $				$ 7,295,000,000		$ 7,046,000,000	7,295,000,000	$ 7,046,000,000
Repurchases of stock and stock settlements of common stock repurchase contracts | $							$ 603,000,000	$ 1,374,000,000	$ 951,000,000
historical stock repurchases, gross, as a percent of shares outstanding at inception of stock repurchase program				38.00%			38.00%
historical stock repurchases, net of new issuances, as a percentage of shares outstanding at inception of stock repurchase program				33.00%			33.00%
Prepaidcommonstockrepurchaseinitialshareamount							0	2,000,000	0
Sale of Stock, Number of Shares Issued in Transaction				0.8
Common Stock [Member]
Number of stock classes							3
Series A Common Stock [Member]
Common Stock, Voting Rights							1
Treasury Stock, Shares				3,000,000			3,000,000
Treasury Stock, Value | $				$ 171,000,000			$ 171,000,000
Series B Common Stock [Member]
Common Stock, Voting Rights							10
Common Stock Conversion Option							1
Stock authorized (in shares)				100,000,000		100,000,000	100,000,000	100,000,000
Preferred stock released from escrow (in shares)				7,000,000		7,000,000	7,000,000	7,000,000
Series C Common Stock [Member]
Treasury Stock, Shares				164,000,000			164,000,000
Treasury Stock, Value | $				$ 6,600,000,000			$ 6,600,000,000
Series A Convertible Preferred Stock [Member]
Temporary equity automatic conversion, percentage				80.00%			80.00%
Convertible preferred stock, liquidation preference | $ / shares				$ 0.01			$ 0.01
Series C Convertible Preferred Stock [Member]
Stock authorized (in shares)				75,000,000			75,000,000
Convertible preferred stock, liquidation preference | $ / shares				$ 0.01			$ 0.01
Additional Paid in Capital | $				$ 0			$ 0
Preferred Stock [Member]
Number of stock classes							2
Series A-1 Preferred Stock [Member]
Stock authorized (in shares)				8,000,000			8,000,000
Series C-1 Preferred Stock [Member] [Domain]
Stock authorized (in shares)				6,000,000			6,000,000
Advance Programming Holdings, LLC [Member]
Preferred stock modification, change in fair value | $				$ 35,000,000
Preferred stock modification, percentage change in fair value					1.05%
Advance Programming Holdings, LLC [Member] | Series A Convertible Preferred Stock [Member]
Preferred Stock, Shares Outstanding						70,673,242		70,673,242
Advance Programming Holdings, LLC [Member] | Series C Convertible Preferred Stock [Member]
Preferred Stock, Shares Outstanding						24,874,370		24,874,370
Preferred stock released from escrow (in shares)														70,000,000
Repurchases of preferred stock, shares							2,300,000	9,100,000
Repurchases of stock and stock settlements of common stock repurchase contracts | $							$ 120,000,000	$ 479,000,000
Preferred Stock, Value, Issued | $											$ 108,000,000
Advance Programming Holdings, LLC [Member] | Series A-1 Preferred Stock [Member]
Preferred Stock, Shares Outstanding										7,852,582
Advance Programming Holdings, LLC [Member] | Series C-1 Preferred Stock [Member] [Domain]
Repurchases of preferred stock, shares							200,000	0
Repurchases of stock and stock settlements of common stock repurchase contracts | $							$ 102,000,000	$ 0
Scenario, Forecast [Member] | Advance Programming Holdings, LLC [Member] | Series C Convertible Preferred Stock [Member]
Repurchases of preferred stock, shares			0
prepaid stock repurchase contract [Member]
Prepaidrepurchaseofcommonstock | $												$ 57,000,000	$ 71,000,000
CashSettlementAmountCommonStockRepurchaseContract | $	$ 58,000,000
Cappriceprepaidstockrepurchasecontract | $ / shares						$ 25.86
PrepaidStockRepurchaseContractValue | $		$ 75,000,000
Prepaidcommonstockrepurchaseinitialshareamount		2,800,000
cashpremiumreceivedcommonstockrepurchasecontract | $	$ 1,000,000
Scenario, conversion of preferred A or A-1 preferred stock to common A stock [Member] [Member] | Advance Programming Holdings, LLC [Member] | Series A Common Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion					70,673,242					70,673,242
Scenario, conversion of preferred C or C-1 preferred stock to common c stock (tranche 1) [Member] | Advance Programming Holdings, LLC [Member] | Series C Common Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion										70,673,242
Series C-1 preferred stock issued in exchange for Series A preferred stock [Member] | Advance Programming Holdings, LLC [Member] | Series C-1 Preferred Stock [Member] [Domain]
Preferred Stock, Shares Outstanding										3,649,573
Scenario, conversion of preferred C or C-1 preferred stock to common c stock [Member] | Advance Programming Holdings, LLC [Member] | Series C Common Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion					70,673,242
Scenario, conversion of preferred C or C-1 preferred stock to common c stock (tranche 2) [Member] | Advance Programming Holdings, LLC [Member] | Series C Common Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion					49,748,740					49,748,740
Series C-1 preferred stock issued in exchange for Series C preferred stock [Member] | Advance Programming Holdings, LLC [Member] | Series C-1 Preferred Stock [Member] [Domain]
Preferred Stock, Shares Outstanding										2,569,020

Equity (Stock Repurchase Progra

Equity (Stock Repurchase Program) (Details) - USD ($) shares in Millions, $ in Millions	Dec. 02, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 15, 2016	Aug. 22, 2016
Equity, Class of Treasury Stock [Line Items]
Repurchases of stock and stock settlements of common stock repurchase contracts		$ 603	$ 1,374	$ 951
Prepaidcommonstockrepurchaseinitialshareamount		0	2	0
Series C Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased		14.3	34.8	23.7
Payments for Repurchase of Common Stock		$ 381	$ 895	$ 698
Advance Programming Holdings, LLC [Member] | Series C Convertible Preferred Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchases of preferred stock, shares		2.3	9.1
Repurchases of stock and stock settlements of common stock repurchase contracts		$ 120	$ 479
prepaid stock repurchase contract [Member]
Equity, Class of Treasury Stock [Line Items]
Prepaidrepurchaseofcommonstock					$ 57	$ 71
Prepaidcommonstockrepurchaseinitialshareamount	2.8
PrepaidStockRepurchaseContractValue	$ 75

Equity (Tax Effects Related To

Equity (Tax Effects Related To Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax	$ 280	$ (234)	$ (249)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax	36	(34)	(33)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(41)	39	23
Other Comprehensive Income (Loss), before Tax	166	(148)	(252)
Other Comprehensive Income (Loss), Foreign Currency Translation Gain (Loss) Arising During Period, Tax	3	41	19
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	(6)	6	6
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	15	(14)	(8)
Other Comprehensive Income (Loss), Tax	12	19	25
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	283	(193)	(230)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	30	(28)	(27)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(26)	25	15
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable	178	(129)	(227)
Currency Translation Adjustments [Member]
Other Comprehensive Income (Loss), before Tax	180	(231)	(220)
Other Comprehensive Income (Loss), Tax	3	40	19
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable	183	(191)	(201)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Other Comprehensive Income (Loss), before Tax	18	45	(31)
Other Comprehensive Income (Loss), Tax	(3)	(7)	6
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable	15	38	(25)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Other Comprehensive Income (Loss), before Tax	(32)	38	(1)
Other Comprehensive Income (Loss), Tax	12	(14)	0
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable	(20)	24	(1)
Gain on Disposition [Member]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, before Tax	12	0	23
Other Comprehensive Income (Loss), Foreign Currency Translation Reclassification Adjustment Realized upon Sale or Liquidation, Tax	0	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax	12	0	23
Other Expense [Member]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, before Tax	0	0	6
Market Value Adjustments And Reclassifications For Securities And Derivatives Before Tax	(17)	(4)	(7)
Other Comprehensive Income (Loss), Foreign Currency Translation Reclassification Adjustment Realized upon Sale or Liquidation, Tax	0	0	0
Market Value Adjustment And Reclassification For Securities And Derivatives Tax Amount	6	1	(2)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax	0	0	6
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	(15)	14	2
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax	0	62	0
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Tax	0	(10)	0
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Net of Tax	0	52	0
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	(11)	(3)	5
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax	(18)	17	2
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	3	(3)	0
Distribution Revenue [Member]
Market Value Adjustments And Reclassifications For Securities And Derivatives Before Tax	22	25	(23)
Market Value Adjustment And Reclassification For Securities And Derivatives Tax Amount	(8)	(7)	8
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	14	18	(15)
Advertising Revenue [Member]
Market Value Adjustments And Reclassifications For Securities And Derivatives Before Tax	3	2	(2)
Market Value Adjustment And Reclassification For Securities And Derivatives Tax Amount	(1)	0	0
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	2	2	(2)
Cost of Sales [Member]
Market Value Adjustments And Reclassifications For Securities And Derivatives Before Tax	0	(27)	(9)
Market Value Adjustment And Reclassification For Securities And Derivatives Tax Amount	0	7	3
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	0	(20)	(6)
Interest Expense [Member]
Market Value Adjustments And Reclassifications For Securities And Derivatives Before Tax	1	3	3
Market Value Adjustment And Reclassification For Securities And Derivatives Tax Amount	0	(1)	(1)
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	1	2	2
Net Investment Hedging [Member]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	0	(1)	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(112)	3	0
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$ (112)	$ (2)	$ 0

Equity (Schedule Of Change In C

Equity (Schedule Of Change In Components Of Accumulated Other Comprehensive Income, Net of Taxes) (Details) - USD ($) $ in Millions	Oct. 01, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Beginning balance		$ (762)
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable		178	$ (129)	$ (227)
Purchase of redeemable noncontrolling interest			(1)	0
Ending balance		(585)	(762)
Currency Translation Adjustments [Member]
Beginning balance		(797)	(606)	(367)
Other comprehensive (loss) income before reclassifications		171	(191)	(230)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		12	0	29
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable		183	(191)	(201)
Purchase of redeemable noncontrolling interest				(61)
Other comprehensive loss (income) attributable to redeemable noncontrolling interests		(1)		23
Ending balance		(615)	(797)	(606)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Beginning balance		11	(27)	(2)
Other comprehensive (loss) income before reclassifications		30	(28)	(27)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(15)	66	2
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable		15	38	(25)
Purchase of redeemable noncontrolling interest				0
Other comprehensive loss (income) attributable to redeemable noncontrolling interests		0		0
Ending balance		26	11	(27)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Beginning balance		24	0	1
Other comprehensive (loss) income before reclassifications		(26)	25	15
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		6	(1)	(16)
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable		(20)	24	(1)
Purchase of redeemable noncontrolling interest				0
Other comprehensive loss (income) attributable to redeemable noncontrolling interests		0		0
Ending balance		4	24	0
Accumulated Other Comprehensive (Loss)/Income [Member]
Beginning balance		(762)	(633)	(368)
Other comprehensive (loss) income before reclassifications		175	(194)	(242)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		3	65	15
Other Comprehensive Income (Loss), Net Of Tax Including Portion Attributable To Redeemable		178	(129)	(227)
Purchase of redeemable noncontrolling interest			0	(61)
Other comprehensive loss (income) attributable to redeemable noncontrolling interests		(1)		23
Ending balance		$ (585)	(762)	(633)
Additional Paid-In Capital [Member]
Purchase of redeemable noncontrolling interest	$ 61		$ 0	$ 61

Equity-Based Compensation (Narr

Equity-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	117,000
Future grant under the incentive plans	97,000
Total liabilities for cash-settled awards	$ 47	$ 83
Current portion of equity-based compensation liabilities	$ 12	$ 31
Performance target for measurement period, years	3 years
PRSU vesting range minimum percentage	0.00%
PRSU vesting range maximum percentage	100.00%
Share-based performance target, percentage	80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 7.99	$ 7.09	$ 8.44
Cash proceeds from equity-based plans, net	$ 42	$ 46	$ 16
Weighted-average fair value Of SARs outstanding	$ 1.01	$ 1.79
Cash payments made to settle vested SARs and Unit Awards	$ (1)	$ (5)	$ (11)
Percentage of common stock closing price for DESPP purchase price	85.00%
Shares issued under DESPP	179	191	208
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Excluding Stock Options	$ 4	$ 4	$ 5
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Settled in period (unit awards)	400
Settled, Weighted-Average Grant Price	$ 35.91
Unrecognized compensation cost	$ 61
Weighted average period of time, in years, compensation expense related to units is expected to be recognized	2 years 263 days
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Settled in period (unit awards)	1,700
Settled, Weighted-Average Grant Price	$ 34.62
Unrecognized compensation cost	$ 21
Weighted average period of time, in years, compensation expense related to units is expected to be recognized	1 year 215 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 32
Weighted average period of time, in years, compensation expense related to units is expected to be recognized	2 years 15 days
Exercised, Aggregate Intrinsic Value	$ 26	$ 42	$ 28
Unit Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Settled in period (unit awards)			1,200
Settled, Weighted-Average Grant Price			$ 20.59
Cash payments made to settle vested SARs and Unit Awards			$ (14)
SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Settled in period (unit awards)	600
Settled, Weighted-Average Grant Price	$ 25.72
Unrecognized compensation cost	$ 4
Weighted average period of time, in years, compensation expense related to units is expected to be recognized	325 days
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	9,000
Minimum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Minimum [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Minimum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	7 years
Maximum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Maximum [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Maximum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years

Equity-Based Compensation (Equi

Equity-Based Compensation (Equity-Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	$ 39	$ 69	$ 35
Tax benefit recognized	9	25	13
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	23	17	17
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	12	13	17
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	6	34	16
SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	(3)	4	(14)
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	1	1	1
Unit Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity-based compensation expense	$ 0	$ 0	$ (2)

Equity-Based Compensation (RSUs

Equity-Based Compensation (RSUs) (Details) - Restricted Stock Units (RSUs) [Member] $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Beginning of Period | shares	2.6
Number of awards granted in period | shares	1.6
Converted in period | shares	(0.4)
Forfeited in Period | shares	(0.4)
Outstanding, End of Period | shares	3.4
Vested and expected to vest as of end of period | shares	3.4
Outstanding as of beginning of period, Weighted-Average Grant Price | $ / shares	$ 30.03
Granted, Weighted-Average Grant Price | $ / shares	28.81
Settled, Weighted-Average Grant Price | $ / shares	35.91
Forfeited, Weighted-Average Grant Price | $ / shares	29.61
Outstanding as of end of period, Weighted-average grant price | $ / shares	$ 28.78
Vested and expected to vest as of end of period, Weighted-Average Remaining Contractual Term (years)	2 years 234 days
Vested and expected to vest as of end of period, Weighted-Average Grant Price | $ / shares	$ 28.78
Outstanding as of end of period, Weighted-Average Remaining Contractual Term (years)	2 years 234 days
Converted, Aggregate Fair Value | $	$ 12
Outstanding as of end of period, Aggregate Fair Value | $	77
Vested and expected to vest as of end of period, Aggregate Fair Value | $	$ 77

Equity-Based Compensation (Stoc

Equity-Based Compensation (Stock Options) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding as of beginning of period	13.7
Granted, Stock Options	2.6
Exercised, Stock Options	(2.5)
Forfeited, Stock Options	(1.5)
Outstanding as of end of period	12.3	13.7
Vested and expected to vest as of beginning of period	12.3
Exercisable as of end of period	6.7
Outstanding as of beginning of period, Weighted-Average Grant Price	$ 26.05
Granted, Weighted-Average Grant Price	28.74
Exercised, Weighted-Average Grant Price	17.54
Forfeited, Weighted-Average Grant Price	33.46
Outstanding as of end of period, Weighted-Average Grant Price	27.46	$ 26.05
Vested and expected to vest, Weighted Average Exercise Price	27.46
Exercisable as of end of period, Weighted-Average Grant Price	$ 26.26
Outstanding as of end of period, Weighted-Average Remaining Contractual Term (years)	3 years 172 days
Vested and expected to vest as of end of period, Weighted-Average Remaining Contractual Term (years)	3 years 172 days
Exercisable as of end of period, Weighted-Average Remaining Contractual Term (years)	2 years 44 days
Exercised, Aggregate Intrinsic Value	$ 26	$ 42	$ 28
Outstanding as of end of period, Aggregate Intrinsic Value	14
Vested and expected to vest as of end of period, Aggregate Intrinsic Value	14
Exercisable as of end of period, Aggregate Intrinsic Value	$ 14

Equity-Based Compensation (Weig

Equity-Based Compensation (Weighted-Average Assumptions Used to Determine Fair Value, Stock Options) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.87%	1.26%	1.54%
Expected term (years)	5 years	5 years	5 years
Expected volatility	27.52%	28.74%	26.78%
Dividend yield	0.00%	0.00%	0.00%

Equity-Based Compensation (PRSU

Equity-Based Compensation (PRSUs) (Details) - Performance Shares [Member] $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Beginning of Period | shares	4.5
Outstanding as of beginning of period, Weighted-Average Grant Price | $ / shares	$ 34.44
Outstanding as of end of period, Weighted-Average Remaining Contractual Term (years)	329 days
Share Based Compensation Arrangement By Share Based Payment Award Other Than Options Unvested Outstanding Aggregate Fair Value | $	$ 76
Number of awards granted in period | shares	0.7
Granted, Weighted-Average Grant Price | $ / shares	$ 29.50
Converted in period | shares	(1.7)
Settled, Weighted-Average Grant Price | $ / shares	$ 34.62
Forfeited in Period | shares	0
Forfeited, Weighted-Average Grant Price | $ / shares	$ 0
Converted, Aggregate Fair Value | $	$ 49
Outstanding, End of Period | shares	3.5
Outstanding as of end of period, Weighted-average grant price | $ / shares	$ 33.41
Vested and expected to vest as of end of period | shares	3.5
Vested and expected to vest as of end of period, Weighted-Average Grant Price | $ / shares	$ 33.41
Vested and expected to vest as of end of period, Weighted-Average Remaining Contractual Term (years)	329 days
Vested and expected to vest as of end of period, Aggregate Fair Value | $	$ 76
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | shares	1.5
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest In Period, Exercisable Weighted Average Grant Date Fair Value | $ / shares	$ 40.42
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value | $	$ 33

Equity-Based Compensation (SARs

Equity-Based Compensation (SARs) (Details) - SARs [Member] $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Beginning of Period | shares	8.6
Number of awards granted in period | shares	3
Settled in period | shares	(0.6)
Forfeited in Period | shares	(3.3)
Outstanding, End of Period | shares	7.7
Vested and expected to vest as of end of period | shares	7.7
Outstanding as of beginning of period, Weighted-Average Grant Price | $ / shares	$ 35.29
Granted, Weighted-Average Grant Price | $ / shares	27.39
Settled, Weighted-Average Grant Price | $ / shares	25.72
Forfeited, Weighted-Average Grant Price | $ / shares	38.60
Outstanding as of end of period, Weighted-average grant price | $ / shares	31.58
Vested and expected to vest as of end of period, Weighted-Average Grant Price | $ / shares	$ 31.58
Outstanding as of end of period, Weighted-Average Remaining Contractual Term (years)	1 year 14 days
Vested and expected to vest as of end of period, Weighted-Average Remaining Contractual Term (years)	1 year 14 days
Settled, Aggregate Intrinsic Value | $	$ 1
Outstanding as of end of period, Aggregate Intrinsic Value | $	0
Vested and expected to vest as of end of period, Aggregate Fair Value | $	$ 0

Equity-Based Compensation (W104

Equity-Based Compensation (Weighted-Average Assumptions Used to Determine Fair Value, SARs) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%
SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.74%	0.95%	0.83%
Expected term (years)	1 year	329 days	329 days
Expected volatility	31.37%	29.46%	31.59%
Dividend yield	0.00%	0.00%	0.00%

Retirement Savings Plans (Detai

Retirement Savings Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Retirement Benefits [Abstract]
Employer matching contributions	$ 30	$ 29	$ 36
Maximum percentage of compensation to SRP	50.00%

Restructuring And Other Char106

Restructuring And Other Charges (Restructuring And Other Charges, By Reporting Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Total restructuring and other charges	$ 75	$ 58	$ 50
U.S. Networks [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and other charges	18	15	33
International Networks [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and other charges	42	26	14
Education And Other [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and other charges	3	3	2
Corporate [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and other charges	$ 12	$ 14	$ 1

Restructuring And Other Char107

Restructuring And Other Charges (Total Restructuring And Other Charges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Restructuring and other charges	$ 68	$ 55	$ 29
ContentImpairmentsInRestructuringAndOtherCharges	7	3	21
Total restructuring and other charges	$ 75	$ 58	$ 50

Restructuring And Other Char108

Restructuring And Other Charges (Restructuring And Other Liabilities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring and other liabilities, Beginning Balance	$ 39	$ 23	$ 19
Restructuring and other charges, net accruals	68	55	29
Restructuring and other charges, cash paid	(64)	(39)	(25)
Restructuring and other liabilities, Beginning Balance, Ending Balance	43	39	23
Contract Termination Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other liabilities, Beginning Balance	3	2	4
Restructuring and other charges, net accruals	3	3	3
Restructuring and other charges, cash paid	(5)	(2)	(5)
Restructuring and other liabilities, Beginning Balance, Ending Balance	1	3	2
Employee Relocation/Terminations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other liabilities, Beginning Balance	36	21	15
Restructuring and other charges, net accruals	65	52	26
Restructuring and other charges, cash paid	(59)	(37)	(20)
Restructuring and other liabilities, Beginning Balance, Ending Balance	$ 42	$ 36	$ 21

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income tax benefit from TCJA	$ 44
Deferred tax assets, net, noncurrent		$ 20
Federal statutory tax rate	35.00%	35.00%	35.00%
Income taxes	$ 176	$ 453	$ 511
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	189	117	173
Unrecognized tax benefits related to tax positions could decrease in next twelve months	53
Accrued interest and penalties on unrecognized tax benefits	$ 21	$ 11	$ 20
Effective Income Tax Rate Reconciliation, Percent	(128.00%)	27.00%	33.00%

Income Taxes (Schedule Of Compo

Income Taxes (Schedule Of Components Of Income From Continuing Operations Before Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Domestic	$ 815	$ 1,414	$ 1,281
Foreign	(952)	257	278
Income before income taxes	$ (137)	$ 1,671	$ 1,559

Income Taxes (Schedule Of Co111

Income Taxes (Schedule Of Components Of Provision For Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal current	$ 177	$ 384	$ 306
State and local taxes, current	45	(56)	57
Foreign current	153	152	146
Current income tax expense	375	480	509
Federal deferred	(124)	45	59
State and local taxes deferred	(7)	0	(10)
Foreign deferred	(68)	(72)	(47)
Deferred income tax expense (benefit)	(199)	(27)	2
Income taxes	$ 176	$ 453	$ 511

Income Taxes (Schedule Of Effec

Income Taxes (Schedule Of Effective Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal income taxes	(18.00%)	(2.00%)	2.00%
Effect of foreign operations	25.00%	(1.00%)	1.00%
Domestic production activity deductions	39.00%	(4.00%)	(3.00%)
Change in uncertain tax positions	(44.00%)	0.00%	(1.00%)
Other, net	4.00%	0.00%	(1.00%)
Effective income tax rate	(128.00%)	27.00%	33.00%
Effective Income Tax Reconciliation, Renewable Energy Investments Tax Credits, Percent	142.00%	(1.00%)	0.00%
Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Percent	32.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent	(9.00%)	0.00%
Effective Income Tax Rate Reconciliations, remeasurement gain on previously held equity interest		0.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent	(334.00%)	(0.00%)

Income Taxes (Components Of Def

Income Taxes (Components Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred tax assets, net, noncurrent		$ 20
Accounts receivable	$ 5	2
Tax attribute carry-forward	151	67
Accrued liabilities and other	190	174
Total deferred income tax assets	346	243
Valuation allowance	(105)	(25)
Net deferred income tax assets	241	218
Intangible assets	(315)	(384)
Content rights	(82)	(166)
Equity method investments	(68)	(76)
Notes receivable	(3)	(7)
Other	(28)	(32)
Total deferred income tax liabilities	(496)	(665)
Deferred Tax Liabilities, Net	$ (255)	$ (447)

Income Taxes (Schedule Of Defer

Income Taxes (Schedule Of Deferred Income Tax Assets And Liabilities In Statement Of Financial Position) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred tax assets, net, noncurrent		$ 20
Deferred Tax Assets, Net	$ 64
Noncurrent deferred income tax liabilities	319	467
Deferred Tax Liabilities, Net	$ (255)	$ (447)

Income Taxes (Schedule of Opera

Income Taxes (Schedule of Operating Loss Carryforwards) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Valuation Allowance, Amount		$ (105)	$ (25)
Federal [Member]
Operating Loss Carryforwards [Line Items]
Valuation Allowance, Amount	[1]	(17)
State [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		176
Deferred Tax Assets, Tax Deferred Expense, Other		12
Valuation Allowance, Amount		(11)
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		1,109
Deferred Tax Assets, Tax Deferred Expense, Other		$ 61
[1]	State ForeignLoss carry-forwards $176 $1,109Deferred tax asset related to loss carry-forwards 12 61Valuation allowance against loss carry-forwards (11) (17)Earliest expiration date of loss carry-forwards 2018 2018

Income Taxes (Schedule Of Unrec

Income Taxes (Schedule Of Unrecognized Tax Benefits Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Beginning balance, unrecognized tax benefits	$ 117	$ 173	$ 176
Additions based on tax positions related to the current year	27	13	30
Additions for tax positions of prior years	57	19	17
Unrecognized Tax Benefits, Increases Resulting from Acquisition	0	0	3
Reductions for tax positions of prior years	0	(60)	(21)
Settlements	(8)	(16)	(16)
Reductions as result of statute lapse	(6)	(9)	(13)
Unrecognized Tax Benefits Additions For Foreign Currency Exchange Rates	2	(3)	(3)
Ending balance, unrecognized tax benefits	$ 189	$ 117	$ 173

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	Aug. 07, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		2
Series C-1 Preferred Stock [Member] [Domain]
Net income available to Discovery Communications, Inc. stockholders, Diluted		$ (71)
Series C Convertible Preferred Stock [Member]
Net income available to Discovery Communications, Inc. stockholders, Diluted			$ 265	$ 234
Series A, B and C Common Stock [Member]
Net income available to Discovery Communications, Inc. stockholders, Diluted		$ (337)	$ 1,194	$ 1,034
Stock Options and RSU [Member] [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		19	8	6
Advance Programming Holdings, LLC [Member] | Series C-1 Preferred Stock [Member] [Domain]
Common Stock, Conversion Basis	19.3648
Advance Programming Holdings, LLC [Member] | Series C Convertible Preferred Stock [Member]
Common Stock, Conversion Basis	2

Earnings Per Share (Reconciliat

Earnings Per Share (Reconciliation of Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net Income available to Discovery Communications, Inc. stockholders	$ (296)	$ 1,055	$ 921
Net income attributable to noncontrolling interests	0	(1)	(1)
Net income	(313)	1,218	1,048
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic	41	(139)	(113)
Net income attributable to noncontrolling interests	0	(1)	(1)
Net (income) loss attributable to redeemable noncontrolling interests	(24)	(23)	(13)
Allocation of undistributed income to Series A convertible preferred stockholders	(41)	139	113
Series A, B and C Common Stock [Member]
Net Income available to Discovery Communications, Inc. stockholders	(225)	789	686
Net income available to Discovery Communications, Inc. stockholders, Diluted	(337)	1,194	1,034
Series C Convertible Preferred Stock [Member]
Net Income available to Discovery Communications, Inc. stockholders	$ (71)	266	235
Net income available to Discovery Communications, Inc. stockholders, Diluted		$ 265	$ 234

Earnings Per Share (Schedule Of

Earnings Per Share (Schedule Of Weighted Average Basic And Diluted Shares Outstanding) (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Series A, B and C Common Stock [Member]
Basic (in shares)	384	401	432
Weighted average impact of assumed preferred stock conversion	192	206	219
Weighted average dilutive effect of equity awards	0	3	5
Weighted average number of shares outstanding, diluted (in shares)	576	610	656
Series C-1 Preferred Stock [Member] [Domain]
Basic (in shares)	6
Series C Convertible Preferred Stock [Member]
Basic (in shares)		7	8
Weighted average number of shares outstanding, diluted (in shares)	6	7	8

Earnings Per Share (Schedule120

Earnings Per Share (Schedule of Basic and Dilutive Earnings Per Share) (Details) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Series A, B and C Common Stock [Member]
Net income per share (in dollars per share)	$ (1.99)	$ 0.38	$ 0.65	$ 0.37	$ 0.52	$ 0.37	$ 0.66	$ 0.42	$ (0.59)	$ 1.97	$ 1.59
Diluted (in dollars per share)	$ (1.99)	$ 0.38	$ 0.64	$ 0.37	$ 0.52	$ 0.36	$ 0.66	$ 0.42	(0.59)	1.96	1.58
Series C-1 Preferred Stock [Member] [Domain]
Net income per share (in dollars per share)									(11.33)
Diluted (in dollars per share)									$ (11.33)
Series C Convertible Preferred Stock [Member]
Net income per share (in dollars per share)										38.07	30.74
Diluted (in dollars per share)										$ 37.88	$ 30.54

Earnings Per Share (Schedule121

Earnings Per Share (Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share) (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share, amount	2
Prepaidcommonstockrepurchaseinitialshareamount	0	2	0
Stock Options and RSU [Member] [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share, amount	19	8	6
Performance Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share, amount	2	4	3

Supplemental Disclosures (Valua

Supplemental Disclosures (Valuation And Qualifying Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance For Doubtful Accounts [Member]
Beginning of Year	$ 47	$ 40	$ 39
Additions	12	13	8
Write-offs	(4)	(6)	(7)
Utilization	0	0	0
End of Year	55	47	40
Deferred Tax Valuation Allowance [Member]
Beginning of Year	25	19	13
Additions	84	9	6
Write-offs	(4)	(3)	0
Utilization	0	0	0
End of Year	$ 105	$ 25	$ 19

Supplemental Disclosures (Sched

Supplemental Disclosures (Schedule Of Accrued Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure Text Block Supplement [Abstract]
Accrued payroll and related benefits	$ 535	$ 486
Program Rights Obligations, Current	219	173
Accrued Interest	148	67
Accrued Income Taxes	45	34
Current portion of equity-based compensation liabilities	12	31
Other accrued liabilities	350	284
Total accrued liabilities	$ 1,309	$ 1,075

Supplemental Disclosures (Sc124

Supplemental Disclosures (Schedule Of Other (Expense) Income, Net) (Details) - USD ($)	12 Months Ended			14 Months Ended	26 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2017
Foreign currency transaction gain (loss), before tax	$ 83,000,000	$ (75,000,000)	$ 103,000,000
Realized loss (gain) from derivative instruments	98,000,000	3,000,000	5,000,000
Remeasurement gain on previously held equity interests	34,000,000	0	2,000,000
Other than Temporary Impairment Losses, Investments	0	(62,000,000)	0
Other (expense) income, net	(110,000,000)	4,000,000	(97,000,000)
Senior Notes, Current	6,800,000,000				$ 6,800,000,000
Other Expense [Member]
Foreign currency transaction gain (loss), before tax	(83,000,000)	75,000,000	(103,000,000)
Realized loss (gain) from derivative instruments	(82,000,000)	(12,000,000)	5,000,000
Remeasurement gain on previously held equity interests	33,000,000	0	2,000,000
Interest Income, Other	21,000,000	0	0
Cost-method Investments, Other than Temporary Impairment	0	62,000,000
Other Nonoperating Income (Expense) Other Net Misc	1,000,000	3,000,000	(1,000,000)
Other (expense) income, net	(110,000,000)	4,000,000	(97,000,000)
Lionsgate [Member]
Other than Temporary Impairment Losses, Investments				$ (62,000,000)	(62,000,000)
Lionsgate [Member] | Other Expense [Member]
Other than Temporary Impairment Losses, Investments			$ 0
Fair Value, Measurements, Recurring [Member] | Cash and Cash Equivalents [Member]
CertificatesOfDepositRestrictedFairValueDisclosure	1,305,000,000				1,305,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member]
Money Market Funds, at Carrying Value	2,700,000,000				2,700,000,000
CertificatesOfDepositRestrictedFairValueDisclosure	0				0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member]
CertificatesOfDepositRestrictedFairValueDisclosure	$ 1,305,000,000	$ 0		$ 0	$ 1,305,000,000

Supplemental Disclosures (Sc125

Supplemental Disclosures (Schedule of Equity-Based Compensation Financing Activities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Tax settlements associated with equity-based plans	$ (30)	$ (11)	$ (27)
Proceeds from Issuance or Sale of Equity	46	50	21
Equity-based plan proceeds, net	$ 16	39	(6)
Adjustments to APIC related to adoption of accounting pronouncements		$ 7	$ 12

Supplemental Disclosures (Suppl

Supplemental Disclosures (Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions	Oct. 01, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Nov. 30, 2017	Nov. 29, 2017	Dec. 21, 2012
Income Taxes Paid, Net			$ 274	$ 527	$ 653
Interest Paid			357	343	312
Fair value of noncash investment			144	0	0
Other Receivables			0	82	0
Business Combination, Consideration Transferred, Other			0	32	0
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability			0	0	13
Capital Expenditures Incurred but Not yet Paid			24	42	12
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Asset			0	0	6
Capital Lease Obligations Incurred			$ 103	$ 37	$ 5
Harpo [Member]
Business Acquisition, Percentage of Voting Interests Acquired						73.99%	49.50%
Eurosport France [Member]
Business Acquisition, Percentage of Voting Interests Acquired		51.00%
Increase or Decrease in ownership, percentage	49.00%	31.00%
Equity Method Investment, Ownership Percentage								20.00%

Related Party Transactions (Nar

Related Party Transactions (Narrative) (Details) - Board of Directors Chairman [Member]	Dec. 31, 2017
Liberty Global [Member]
Related Party Transaction [Line Items]
Aggregate equity voting power percentage	26.00%
Liberty Broadband [Member]
Related Party Transaction [Line Items]
Aggregate equity voting power percentage	46.00%

Related Party Transactions (Sch

Related Party Transactions (Schedule of Related Party Transactions, Revenue) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Related Party Transaction, Revenues from Transactions with Related Party	$ 667	$ 548	$ 268
Related Party Transaction, Expenses from Transactions with Related Party	(178)	(102)	(67)
Liberty Group [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Revenues from Transactions with Related Party	476	387	171
Equity Method Investments [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Revenues from Transactions with Related Party	145	129	62
Interest and Other Income	13	17	23
Other Related Parties [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Revenues from Transactions with Related Party	$ 46	$ 32	$ 35

Related Party Transactions (129

Related Party Transactions (Schedule of Related Party Transactions Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Due from Related Parties, Current	$ 105	$ 109
OWN Joint Venture [Member]
Related Party Transaction [Line Items]
Advances to and note receivable from OWN	$ 0	$ 311

Commitments And Contingencie130

Commitments And Contingencies (Narrative) (Details) € in Millions	Oct. 01, 2015USD ($)	Oct. 01, 2015EUR (€)	Sep. 30, 2015USD ($)	Dec. 31, 2022	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jul. 22, 2015EUR (€)	Dec. 31, 2014USD ($)
Commitments and Contingencies [Line Items]
Put right obligations						$ 0
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					$ 413,000,000	243,000,000	$ 241,000,000		$ 747,000,000
Derivative, Term of Contract					1 year
RedeemableNoncontrollingInterestDecreaseFromRedemptions			$ 551,000,000		$ 0	0	551,000,000
Purchase of redeemable noncontrolling interests					0	0	$ 548,000,000
Material amounts for indemnifications or other contingencies					$ 0	0
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]					The following table summarizes the adjustments the Company made to conform prior period classifications to the new guidance: December 31, 2016 As reported As adjusted Current deferred income tax assets $ 97 $ — Noncurrent deferred income tax assets (included within other noncurrent assets) 9 20 Noncurrent deferred income tax liabilities (553 ) (467 ) Total $ (447 ) $ (447 )
Loss Contingency Accrual, at Carrying Value					$ 0	$ 0
Eurosport [Member]
Commitments and Contingencies [Line Items]
Increase or Decrease in ownership, percentage	49.00%	49.00%
MandatorilyRedeemableNoncontrollinginterestreclassifiedtocurrentliabilities | €								€ 491
Purchase of redeemable noncontrolling interests	$ 548,000,000	€ 491
Discovery Family [Member]
Commitments and Contingencies [Line Items]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					210,000,000
VTEN [Member]
Commitments and Contingencies [Line Items]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					120,000,000
Harpo [Member]
Commitments and Contingencies [Line Items]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					55,000,000
Discovery Japan [Member]
Commitments and Contingencies [Line Items]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests					$ 27,000,000
Scenario, Forecast [Member] | Discovery Family [Member]
Commitments and Contingencies [Line Items]
Derivative, Term of Contract				1 year

Commitments And Contingencie131

Commitments And Contingencies (Schedule Of Significant Contractual Commitments) (Details) $ in Millions	Dec. 31, 2017USD ($)
2,018	$ 1,516
2,019	887
2,020	994
2,021	454
2,022	419
Thereafter	991
Total minimum payments	5,261
Less amounts representing interest	(40)
Total	5,221
Operating Lease [Member]
2,018	61
2,019	52
2,020	36
2,021	28
2,022	17
Thereafter	36
Operating Leases, Future Minimum Payments Due	230
Less amounts representing interest	0
Total	230
Capital Lease [Member]
2,018	48
2,019	36
2,020	33
2,021	30
2,022	23
Thereafter	95
Capital Leases, Future Minimum Payments Due	265
Less amounts representing interest	(40)
Total	225
Content [Member]
2,018	1,075
2,019	558
2,020	750
2,021	342
2,022	350
Thereafter	771
Total minimum payments	3,846
Less amounts representing interest	0
Total	3,846
Other Credit Derivatives [Member]
2,018	332
2,019	241
2,020	175
2,021	54
2,022	29
Thereafter	89
Total minimum payments	920
Less amounts representing interest	0
Total	$ 920

Reportable Segments (Details)

Reportable Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Amortization of deferred launch incentives	$ 3	$ 13	$ 16

Reportable Segments (Schedule O

Reportable Segments (Schedule Of Revenues By Segment) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 1,864	$ 1,651	$ 1,745	$ 1,613	$ 1,672	$ 1,556	$ 1,708	$ 1,561	$ 6,873	$ 6,497	$ 6,394
U.S. Networks [Member]
Segment Reporting Information [Line Items]
Revenues by Segment									3,434	3,285	3,131
International Networks [Member]
Segment Reporting Information [Line Items]
Revenues by Segment									3,281	3,040	3,092
Education And Other [Member]
Segment Reporting Information [Line Items]
Revenues by Segment									158	174	173
Corporate And Inter-Segment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues by Segment									$ 0	$ (2)	$ (2)

Reportable Segments (Schedul134

Reportable Segments (Schedule Of Adjusted OIBDA By Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total Adjusted OIBDA	$ 2,531	$ 2,413	$ 2,382
U.S. Networks [Member]
Segment Reporting Information [Line Items]
Total Adjusted OIBDA	2,026	1,922	1,774
International Networks [Member]
Segment Reporting Information [Line Items]
Total Adjusted OIBDA	859	835	945
Education And Other [Member]
Segment Reporting Information [Line Items]
Total Adjusted OIBDA	6	(10)	(2)
Corporate And Inter-Segment Eliminations [Member]
Segment Reporting Information [Line Items]
Total Adjusted OIBDA	$ (360)	$ (334)	$ (335)

Reportable Segments (Schedul135

Reportable Segments (Schedule Of Reconciliation Of Adjusted OIDBA To Operating Income) (Details) - USD ($)	Nov. 30, 2016	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Net income attributable to Discovery Communications, Inc.		$ (1,144,000,000)	$ 218,000,000	$ 374,000,000	$ 215,000,000	$ 304,000,000	$ 219,000,000	$ 408,000,000	$ 263,000,000	$ (337,000,000)	$ 1,194,000,000	$ 1,034,000,000
Net (income) loss attributable to redeemable noncontrolling interests										24,000,000	23,000,000	13,000,000
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest										0	1,000,000	1,000,000
Income taxes										176,000,000	453,000,000	511,000,000
Income before income taxes										(137,000,000)	1,671,000,000	1,559,000,000
Other (expense) income, net										110,000,000	(4,000,000)	97,000,000
Income from equity investees, net										211,000,000	38,000,000	(1,000,000)
Loss on extinguishment of debt										54,000,000	0	0
Interest Expense, Debt										475,000,000	353,000,000	330,000,000
Operating income		(837,000,000)	$ 433,000,000	$ 630,000,000	$ 487,000,000	$ 525,000,000	$ 458,000,000	$ 586,000,000	$ 489,000,000	713,000,000	2,058,000,000	1,985,000,000
Gain (loss) on disposition										4,000,000	(63,000,000)	17,000,000
Restructuring and impairment charges										75,000,000	58,000,000	50,000,000
Depreciation and amortization										330,000,000	322,000,000	330,000,000
Impairment of goodwill	$ 0	$ 1,300,000,000								1,327,000,000	0	0
Mark-to-market stock-based compensation										3,000,000	38,000,000	0
Scripps Networks transaction and integration costs										79,000,000	0	0
Amortization of deferred launch incentives										3,000,000	13,000,000	16,000,000
Total Adjusted OIBDA										$ 2,531,000,000	$ 2,413,000,000	$ 2,382,000,000

Reportable Segments (Schedul136

Reportable Segments (Schedule Of Total Assets By Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total assets	$ 22,555	$ 15,672
U.S. Networks [Member]
Segment Reporting Information [Line Items]
Total assets	4,127	3,412
International Networks [Member]
Segment Reporting Information [Line Items]
Total assets	5,187	4,922
Education And Other [Member]
Segment Reporting Information [Line Items]
Total assets	394	399
Corporate And Inter-Segment Eliminations [Member]
Segment Reporting Information [Line Items]
Total assets	$ 12,847	$ 6,939

Reportable Segments (Schedul137

Reportable Segments (Schedule Of Content Amortization And Impairment Expense By Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total content amortization and impairment expense	$ 1,910	$ 1,773	$ 1,709
U.S. Networks [Member]
Segment Reporting Information [Line Items]
Total content amortization and impairment expense	776	756	771
International Networks [Member]
Segment Reporting Information [Line Items]
Total content amortization and impairment expense	1,126	1,008	931
Education And Other [Member]
Segment Reporting Information [Line Items]
Total content amortization and impairment expense	$ 8	$ 9	$ 7

Reportable Segments (Schedul138

Reportable Segments (Schedule Of Revenues By Country) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 1,864	$ 1,651	$ 1,745	$ 1,613	$ 1,672	$ 1,556	$ 1,708	$ 1,561	$ 6,873	$ 6,497	$ 6,394
United States [Member]
Segment Reporting Information [Line Items]
Total revenues									3,560	3,411	3,261
Non-U.S [Member]
Segment Reporting Information [Line Items]
Total revenues									$ 3,313	$ 3,086	$ 3,133

Reportable Segments (Schedul139

Reportable Segments (Schedule Of Property And Equipment By Country) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Property and equipment, net	$ 597	$ 482
United States [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	309	258
United Kingdom
Segment Reporting Information [Line Items]
Property and equipment, net	173	107
Other Non U.S.
Segment Reporting Information [Line Items]
Property and equipment, net	$ 115	$ 117

Selected Quarterly Financial140

Selected Quarterly Financial Data (Unaudited) (Details) - USD ($)	Nov. 30, 2017	Apr. 28, 2017	Dec. 02, 2016	Nov. 30, 2016	Oct. 01, 2015	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2017	Nov. 29, 2017	Sep. 25, 2017	Mar. 13, 2017
Impairment of goodwill				$ 0		$ 1,300,000,000								$ 1,327,000,000	$ 0	$ 0
Other-than-temporary impairment of AFS investments														0	62,000,000	0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal														(4,000,000)	63,000,000	(17,000,000)
Scripps Networks transaction and integration costs														79,000,000	0	0
Business Combination, Consideration Transferred, Other														0	32,000,000	0
Total revenues						1,864,000,000	$ 1,651,000,000	$ 1,745,000,000	$ 1,613,000,000	$ 1,672,000,000	$ 1,556,000,000	$ 1,708,000,000	$ 1,561,000,000	6,873,000,000	6,497,000,000	6,394,000,000
Operating income						(837,000,000)	433,000,000	630,000,000	487,000,000	525,000,000	458,000,000	586,000,000	489,000,000	713,000,000	2,058,000,000	1,985,000,000
Net income						(1,137,000,000)	223,000,000	380,000,000	221,000,000	309,000,000	225,000,000	415,000,000	269,000,000	(313,000,000)	1,218,000,000	1,048,000,000
Net income attributable to Discovery Communications, Inc.						(1,144,000,000)	$ 218,000,000	$ 374,000,000	$ 215,000,000	304,000,000	$ 219,000,000	$ 408,000,000	$ 263,000,000	(337,000,000)	1,194,000,000	1,034,000,000
Net income														(313,000,000)	1,218,000,000	1,048,000,000
Long-term Debt, Gross						$ 14,913,000,000				$ 7,990,000,000				14,913,000,000	7,990,000,000		$ 7,990,000,000	$ 14,913,000,000
Gain (Loss) on Extinguishment of Debt														(54,000,000)	0	0
Payment for Debt Extinguishment or Debt Prepayment Cost														50,000,000
Write off of Deferred Debt Issuance Cost														2,000,000
Repayments of Debt														1,000,000
Payments of Debt Issuance Costs														1,000,000
Remeasurement gain on previously held equity interests														$ 34,000,000	$ 0	$ 2,000,000
Series A, B and C Common Stock [Member]
Basic earnings per share available to Discovery Communications, Inc. stockholders
Net income per share (in dollars per share)						$ (1.99)	$ 0.38	$ 0.65	$ 0.37	$ 0.52	$ 0.37	$ 0.66	$ 0.42	$ (0.59)	$ 1.97	$ 1.59
Diluted earnings per share available to Discovery Communications, Inc. stockholders
Diluted (in dollars per share)						$ (1.99)	$ 0.38	$ 0.64	$ 0.37	$ 0.52	$ 0.36	$ 0.66	$ 0.42	$ (0.59)	$ 1.96	$ 1.58
VTEN [Member]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity																				67.50%
Eurosport [Member]
Increase or Decrease in ownership, percentage					49.00%
Harpo [Member]
Business Acquisition, Percentage of Voting Interests Acquired	73.99%																		49.50%
Cash consideration transferred	$ 70,000,000
Remeasurement gain on previously held equity interests	$ 33,000,000
Raw Betty [Member]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal														$ 4,000,000
Business Combination, Consideration Transferred, Other		$ 38,000,000
Lionsgate [Member]
Other-than-temporary impairment of AFS investments																	62,000,000	$ 62,000,000
GroupNineMediaJV [Member]
Noncontrolling Interest, Ownership Percentage by Parent			39.00%			42.00%								42.00%				42.00%
Business Combination, Consideration Transferred			$ 100,000,000
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal			50,000,000
Business Combination, Consideration Transferred, Other			$ 32,000,000
Advance Programming Holdings, LLC [Member]
Preferred stock modification, change in fair value						$ 35,000,000
5.05% Senior Notes [Member]
Long-term Debt, Gross						$ 789,000,000				$ 1,300,000,000				$ 789,000,000	$ 1,300,000,000		1,300,000,000	$ 789,000,000			$ 600,000,000
Debt instrument interest rate						5.05%			5.05%					5.05%				5.05%
Five Point Six Two Five Percent Senior Notes [Member]
Long-term Debt, Gross						$ 411,000,000				$ 500,000,000				$ 411,000,000	$ 500,000,000		$ 500,000,000	$ 411,000,000
Debt instrument interest rate						5.625%			5.625%					5.625%				5.625%

Condensed Consolidating Fina141

Condensed Consolidating Financial Statements (Narrative) (Details)	Dec. 31, 2017	Sep. 25, 2017
Business Acquisition [Line Items]
Direct ownership percentage in Discovery Communications Holding, LLC	33.30%
Indirect ownership percentage in Discovery Communications Holding, LLC	66.70%
VTEN [Member]
Business Acquisition [Line Items]
Business combination, Post-acquisition ownership percentage of the Acquiror in the Combined Entity		67.50%

Condensed Consolidating Fina142

Condensed Consolidating Financial Statements (Condensed Consolidating Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash and cash equivalents	$ 7,309	$ 300	$ 390	$ 367
Receivables, net	1,838	1,495
Content rights, net	410	310
Deferred income taxes		0
Prepaid expenses and other current assets	434	397
Total current assets	9,991	2,502
Noncurrent content rights, net	2,213	2,089
Goodwill	7,073	8,040	8,164
Intangible assets, net	1,770	1,512
Equity method investments	335	557
Other noncurrent assets	576	490
Total assets	22,555	15,672
Current portion of debt	30	82
Total current liabilities	1,871	1,561
Noncurrent portion of debt	14,755	7,841
Other noncurrent liabilities	587	393
Total liabilities	17,532	10,262
Redeemable noncontrolling interests	413	243
Total liabilities and equity	22,555	15,672
Reclassifications and Eliminations [Member]
Cash and cash equivalents	0	0	0	0
Receivables, net	0	0
Content rights, net	0	0
Prepaid expenses and other current assets	0	0
Intercompany Trade Receivables, Net	(205)	(195)
Total current assets	(205)	(195)
Investment in and advances to subsidiaries	(19,102)	(21,043)
Noncurrent content rights, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Equity method investments	0	0
Other noncurrent assets	(20)	(20)
Total assets	(19,327)	(21,258)
Current portion of debt	0	0
Other current liabilities	0	0
Intercompany Trade Payables, Net	(205)	(195)
Total current liabilities	(205)	(195)
Noncurrent portion of debt	0	0
Other noncurrent liabilities	(20)	(20)
Total liabilities	(225)	(215)
Redeemable noncontrolling interests	0	0
Equity attributable to Discovery Communications, Inc.	(19,102)	(21,043)
Total liabilities and equity	(19,327)	(21,258)
Discovery [Member]
Cash and cash equivalents	0	0	0	0
Receivables, net	0	0
Content rights, net	0	0
Prepaid expenses and other current assets	49	62
Intercompany Trade Receivables, Net	0	0
Total current assets	49	62
Investment in and advances to subsidiaries	4,563	5,106
Noncurrent content rights, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Equity method investments	0	0
Other noncurrent assets	0	0
Total assets	4,612	5,168
Current portion of debt	0	0
Other current liabilities	0	0
Intercompany Trade Payables, Net	0	0
Total current liabilities	0	0
Noncurrent portion of debt	0	0
Other noncurrent liabilities	2	1
Total liabilities	2	1
Redeemable noncontrolling interests	0	0
Equity attributable to Discovery Communications, Inc.	4,610	5,167
Total liabilities and equity	4,612	5,168
DCH [Member]
Cash and cash equivalents	0	0	0	0
Receivables, net	0	0
Content rights, net	0	0
Prepaid expenses and other current assets	32	36
Intercompany Trade Receivables, Net	0	0
Total current assets	32	36
Investment in and advances to subsidiaries	4,532	5,070
Noncurrent content rights, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Equity method investments	0	0
Other noncurrent assets	20	20
Total assets	4,584	5,126
Current portion of debt	0	0
Other current liabilities	0	0
Intercompany Trade Payables, Net	0	0
Total current liabilities	0	0
Noncurrent portion of debt	0	0
Other noncurrent liabilities	0	0
Total liabilities	0	0
Redeemable noncontrolling interests	0	0
Equity attributable to Discovery Communications, Inc.	4,584	5,126
Total liabilities and equity	4,584	5,126
DCL [Member]
Cash and cash equivalents	6,800	20	3	8
Receivables, net	410	421
Content rights, net	4	8
Prepaid expenses and other current assets	204	180
Intercompany Trade Receivables, Net	205	195
Total current assets	7,623	824
Investment in and advances to subsidiaries	6,951	7,450
Noncurrent content rights, net	672	663
Goodwill	3,677	3,769
Intangible assets, net	259	272
Equity method investments	25	30
Other noncurrent assets	364	306
Total assets	19,571	13,314
Current portion of debt	7	52
Other current liabilities	572	516
Intercompany Trade Payables, Net	0	0
Total current liabilities	579	568
Noncurrent portion of debt	14,163	7,315
Other noncurrent liabilities	297	361
Total liabilities	15,039	8,244
Redeemable noncontrolling interests	0	0
Equity attributable to Discovery Communications, Inc.	4,532	5,070
Total liabilities and equity	19,571	13,314
Non-Guarantor Subsidiaries Of DCL [Member]
Cash and cash equivalents	509	280	387	359
Receivables, net	1,428	1,074
Content rights, net	406	302
Prepaid expenses and other current assets	149	119
Intercompany Trade Receivables, Net	0	0
Total current assets	2,492	1,775
Investment in and advances to subsidiaries	0	0
Noncurrent content rights, net	1,541	1,426
Goodwill	3,396	4,271
Intangible assets, net	1,511	1,240
Equity method investments	310	527
Other noncurrent assets	809	666
Total assets	10,059	9,905
Current portion of debt	23	30
Other current liabilities	1,269	963
Intercompany Trade Payables, Net	205	195
Total current liabilities	1,497	1,188
Noncurrent portion of debt	592	526
Other noncurrent liabilities	606	498
Total liabilities	2,695	2,212
Redeemable noncontrolling interests	413	243
Equity attributable to Discovery Communications, Inc.	6,951	7,450
Total liabilities and equity	10,059	9,905
Other Non - Guarantor Subsidiaries Of Discovery [Member]
Cash and cash equivalents	0	0	0	0
Receivables, net	0	0
Content rights, net	0	0
Prepaid expenses and other current assets	0	0
Intercompany Trade Receivables, Net	0	0
Total current assets	0	0
Investment in and advances to subsidiaries	3,056	3,417
Noncurrent content rights, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Equity method investments	0	0
Other noncurrent assets	0	0
Total assets	3,056	3,417
Current portion of debt	0	0
Other current liabilities	0	0
Intercompany Trade Payables, Net	0	0
Total current liabilities	0	0
Noncurrent portion of debt	0	0
Other noncurrent liabilities	21	20
Total liabilities	21	20
Redeemable noncontrolling interests	0	0
Equity attributable to Discovery Communications, Inc.	3,035	3,397
Total liabilities and equity	3,056	3,417
Discovery and Subsidiaries [Member]
Cash and cash equivalents	7,309	300	$ 390	$ 367
Receivables, net	1,838	1,495
Content rights, net	410	310
Prepaid expenses and other current assets	434	397
Intercompany Trade Receivables, Net	0	0
Total current assets	9,991	2,502
Investment in and advances to subsidiaries	0	0
Noncurrent content rights, net	2,213	2,089
Goodwill	7,073	8,040
Intangible assets, net	1,770	1,512
Equity method investments	335	557
Other noncurrent assets	1,173	972
Total assets	22,555	15,672
Current portion of debt	30	82
Other current liabilities	1,841	1,479
Intercompany Trade Payables, Net	0	0
Total current liabilities	1,871	1,561
Noncurrent portion of debt	14,755	7,841
Other noncurrent liabilities	906	860
Total liabilities	17,532	10,262
Redeemable noncontrolling interests	413	243
Equity attributable to Discovery Communications, Inc.	4,610	5,167
Total liabilities and equity	$ 22,555	$ 15,672

Condensed Consolidating Fina143

Condensed Consolidating Financial Statements (Condensed Consolidating Statement Of Operations) (Details) - USD ($)	Nov. 30, 2016	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues		$ 1,864,000,000	$ 1,651,000,000	$ 1,745,000,000	$ 1,613,000,000	$ 1,672,000,000	$ 1,556,000,000	$ 1,708,000,000	$ 1,561,000,000	$ 6,873,000,000	$ 6,497,000,000	$ 6,394,000,000
Costs of revenues, excluding depreciation and amortization										2,656,000,000	2,432,000,000	2,343,000,000
Selling, general and administrative										1,768,000,000	1,690,000,000	1,669,000,000
Goodwill, Impairment Loss	$ 0	1,300,000,000								1,327,000,000	0	0
Depreciation and amortization										330,000,000	322,000,000	330,000,000
Restructuring and other charges										75,000,000	58,000,000	50,000,000
Loss (gain) on disposition										4,000,000	(63,000,000)	17,000,000
Total costs and expenses										6,160,000,000	4,439,000,000	4,409,000,000
Operating income		(837,000,000)	433,000,000	630,000,000	487,000,000	525,000,000	458,000,000	586,000,000	489,000,000	713,000,000	2,058,000,000	1,985,000,000
Interest expense										(475,000,000)	(353,000,000)	(330,000,000)
Loss on extinguishment of debt										(54,000,000)	0	0
(Loss) income from equity investees, net										(211,000,000)	(38,000,000)	1,000,000
Other (expense) income, net										(110,000,000)	4,000,000	(97,000,000)
Income before income taxes										(137,000,000)	1,671,000,000	1,559,000,000
Income taxes										(176,000,000)	(453,000,000)	(511,000,000)
Net income		(1,137,000,000)	223,000,000	380,000,000	221,000,000	309,000,000	225,000,000	415,000,000	269,000,000	(313,000,000)	1,218,000,000	1,048,000,000
Net income attributable to noncontrolling interests										0	(1,000,000)	(1,000,000)
Net income attributable to redeemable noncontrolling interests										(24,000,000)	(23,000,000)	(13,000,000)
Net income attributable to Discovery Communications, Inc.		$ (1,144,000,000)	$ 218,000,000	$ 374,000,000	$ 215,000,000	$ 304,000,000	$ 219,000,000	$ 408,000,000	$ 263,000,000	(337,000,000)	1,194,000,000	1,034,000,000
Reclassifications and Eliminations [Member]
Revenues										(12,000,000)	(13,000,000)	(13,000,000)
Costs of revenues, excluding depreciation and amortization										(2,000,000)	(4,000,000)	(4,000,000)
Selling, general and administrative										(10,000,000)	(9,000,000)	(9,000,000)
Goodwill, Impairment Loss										0
Depreciation and amortization										0	0	0
Restructuring and other charges										0	0	0
Loss (gain) on disposition										0	0	0
Total costs and expenses										(12,000,000)	(13,000,000)	(13,000,000)
Operating income										0	0	0
Equity in earnings of subsidiaries										1,309,000,000	(3,810,000,000)	(3,289,000,000)
Interest expense										0	0	0
Loss on extinguishment of debt										0
(Loss) income from equity investees, net										0	0	0
Other (expense) income, net										0	0	0
Income before income taxes										1,309,000,000	(3,810,000,000)	(3,289,000,000)
Income taxes										0	0	0
Net income										1,309,000,000	(3,810,000,000)	(3,289,000,000)
Net income attributable to noncontrolling interests											(1,000,000)	(1,000,000)
Net income attributable to redeemable noncontrolling interests										(24,000,000)	(23,000,000)	(13,000,000)
Net income attributable to Discovery Communications, Inc.										1,285,000,000	(3,834,000,000)	(3,303,000,000)
Discovery [Member]
Revenues										0	0	0
Costs of revenues, excluding depreciation and amortization										0	0	0
Selling, general and administrative										53,000,000	14,000,000	15,000,000
Goodwill, Impairment Loss										0
Depreciation and amortization										0	0	0
Restructuring and other charges										0	0	0
Loss (gain) on disposition										0	0	0
Total costs and expenses										53,000,000	14,000,000	15,000,000
Operating income										(53,000,000)	(14,000,000)	(15,000,000)
Equity in earnings of subsidiaries										(288,000,000)	1,203,000,000	1,044,000,000
Interest expense										0	0	0
Loss on extinguishment of debt										0
(Loss) income from equity investees, net										0	0	0
Other (expense) income, net										0	0	0
Income before income taxes										(341,000,000)	1,189,000,000	1,029,000,000
Income taxes										4,000,000	5,000,000	5,000,000
Net income										(337,000,000)	1,194,000,000	1,034,000,000
Net income attributable to noncontrolling interests											0	0
Net income attributable to redeemable noncontrolling interests										0	0	0
Net income attributable to Discovery Communications, Inc.										(337,000,000)	1,194,000,000	1,034,000,000
DCH [Member]
Revenues										0	0	0
Costs of revenues, excluding depreciation and amortization										0	0	0
Selling, general and administrative										0	0	0
Goodwill, Impairment Loss										0
Depreciation and amortization										0	0	0
Restructuring and other charges										0	0	0
Loss (gain) on disposition										0	0	0
Total costs and expenses										0	0	0
Operating income										0	0	0
Equity in earnings of subsidiaries										(288,000,000)	1,203,000,000	1,044,000,000
Interest expense										0	0	0
Loss on extinguishment of debt										0
(Loss) income from equity investees, net										0	0	0
Other (expense) income, net										0	0	0
Income before income taxes										(288,000,000)	1,203,000,000	1,044,000,000
Income taxes										0	0	0
Net income										(288,000,000)	1,203,000,000	1,044,000,000
Net income attributable to noncontrolling interests											0	0
Net income attributable to redeemable noncontrolling interests										0	0	0
Net income attributable to Discovery Communications, Inc.										(288,000,000)	1,203,000,000	1,044,000,000
DCL [Member]
Revenues										1,988,000,000	1,963,000,000	1,909,000,000
Costs of revenues, excluding depreciation and amortization										467,000,000	466,000,000	500,000,000
Selling, general and administrative										309,000,000	292,000,000	265,000,000
Goodwill, Impairment Loss										0
Depreciation and amortization										42,000,000	41,000,000	35,000,000
Restructuring and other charges										35,000,000	28,000,000	28,000,000
Loss (gain) on disposition										0	(50,000,000)	0
Total costs and expenses										853,000,000	777,000,000	828,000,000
Operating income										1,135,000,000	1,186,000,000	1,081,000,000
Equity in earnings of subsidiaries										(541,000,000)	602,000,000	505,000,000
Interest expense										(448,000,000)	(332,000,000)	(318,000,000)
Loss on extinguishment of debt										(54,000,000)
(Loss) income from equity investees, net										(3,000,000)	(3,000,000)	4,000,000
Other (expense) income, net										(204,000,000)	40,000,000	9,000,000
Income before income taxes										(115,000,000)	1,493,000,000	1,281,000,000
Income taxes										(173,000,000)	(290,000,000)	(237,000,000)
Net income										(288,000,000)	1,203,000,000	1,044,000,000
Net income attributable to noncontrolling interests											0	0
Net income attributable to redeemable noncontrolling interests										0	0	0
Net income attributable to Discovery Communications, Inc.										(288,000,000)	1,203,000,000	1,044,000,000
Non-Guarantor Subsidiaries Of DCL [Member]
Revenues										4,897,000,000	4,547,000,000	4,498,000,000
Costs of revenues, excluding depreciation and amortization										2,191,000,000	1,970,000,000	1,847,000,000
Selling, general and administrative										1,416,000,000	1,393,000,000	1,398,000,000
Goodwill, Impairment Loss										1,327,000,000
Depreciation and amortization										288,000,000	281,000,000	295,000,000
Restructuring and other charges										40,000,000	30,000,000	22,000,000
Loss (gain) on disposition										4,000,000	(13,000,000)	17,000,000
Total costs and expenses										5,266,000,000	3,661,000,000	3,579,000,000
Operating income										(369,000,000)	886,000,000	919,000,000
Equity in earnings of subsidiaries										0	0	0
Interest expense										(27,000,000)	(21,000,000)	(12,000,000)
Loss on extinguishment of debt										0
(Loss) income from equity investees, net										(208,000,000)	(35,000,000)	(3,000,000)
Other (expense) income, net										94,000,000	(36,000,000)	(106,000,000)
Income before income taxes										(510,000,000)	794,000,000	798,000,000
Income taxes										(7,000,000)	(168,000,000)	(279,000,000)
Net income										(517,000,000)	626,000,000	519,000,000
Net income attributable to noncontrolling interests											0	0
Net income attributable to redeemable noncontrolling interests										0	0	0
Net income attributable to Discovery Communications, Inc.										(517,000,000)	626,000,000	519,000,000
Other Non - Guarantor Subsidiaries Of Discovery [Member]
Revenues										0	0	0
Costs of revenues, excluding depreciation and amortization										0	0	0
Selling, general and administrative										0	0	0
Goodwill, Impairment Loss										0
Depreciation and amortization										0	0	0
Restructuring and other charges										0	0	0
Loss (gain) on disposition										0	0	0
Total costs and expenses										0	0	0
Operating income										0	0	0
Equity in earnings of subsidiaries										(192,000,000)	802,000,000	696,000,000
Interest expense										0	0	0
Loss on extinguishment of debt										0
(Loss) income from equity investees, net										0	0	0
Other (expense) income, net										0	0	0
Income before income taxes										(192,000,000)	802,000,000	696,000,000
Income taxes										0	0	0
Net income										(192,000,000)	802,000,000	696,000,000
Net income attributable to noncontrolling interests											0	0
Net income attributable to redeemable noncontrolling interests										0	0	0
Net income attributable to Discovery Communications, Inc.										(192,000,000)	802,000,000	696,000,000
Discovery and Subsidiaries [Member]
Revenues										6,873,000,000	6,497,000,000	6,394,000,000
Costs of revenues, excluding depreciation and amortization										2,656,000,000	2,432,000,000	2,343,000,000
Selling, general and administrative										1,768,000,000	1,690,000,000	1,669,000,000
Goodwill, Impairment Loss										1,327,000,000
Depreciation and amortization										330,000,000	322,000,000	330,000,000
Restructuring and other charges										75,000,000	58,000,000	50,000,000
Loss (gain) on disposition										4,000,000	(63,000,000)	17,000,000
Total costs and expenses										6,160,000,000	4,439,000,000	4,409,000,000
Operating income										713,000,000	2,058,000,000	1,985,000,000
Equity in earnings of subsidiaries										0	0	0
Interest expense										(475,000,000)	(353,000,000)	(330,000,000)
Loss on extinguishment of debt										(54,000,000)
(Loss) income from equity investees, net										(211,000,000)	(38,000,000)	1,000,000
Other (expense) income, net										(110,000,000)	4,000,000	(97,000,000)
Income before income taxes										(137,000,000)	1,671,000,000	1,559,000,000
Income taxes										(176,000,000)	(453,000,000)	(511,000,000)
Net income										(313,000,000)	1,218,000,000	1,048,000,000
Net income attributable to noncontrolling interests											(1,000,000)	(1,000,000)
Net income attributable to redeemable noncontrolling interests										(24,000,000)	(23,000,000)	(13,000,000)
Net income attributable to Discovery Communications, Inc.										$ (337,000,000)	$ 1,194,000,000	$ 1,034,000,000

Condensed Consolidating Fina144

Condensed Consolidating Financial Statements (Condensed Consolidating Statement of Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									$ (40)	$ 0	$ 0
Payments of Ordinary Dividends, Noncontrolling Interest									30	22	42
Payments for investments, net											(272)
Net income	$ (1,137)	$ 223	$ 380	$ 221	$ 309	$ 225	$ 415	$ 269	(313)	1,218	1,048
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(135)	1,089	821
Comprehensive income attributable to noncontrolling interests									0	(1)	(1)
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(25)	(23)	10
Comprehensive income attributable to Discovery Communications Inc.									(160)	1,065	830
Reclassifications and Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									0
Payments of Ordinary Dividends, Noncontrolling Interest									0	0	0
Payments for investments, net									0		0
Net income									1,309	(3,810)	(3,289)
Currency translation adjustments									(674)	699	735
Market value adjustments									(55)	(139)	92
Derivative adjustments									62	(86)	6
Comprehensive income									642	(3,336)	(2,456)
Comprehensive income attributable to noncontrolling interests										(1)	(1)
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(20)	84	(97)
Comprehensive income attributable to Discovery Communications Inc.									622	(3,253)	(2,554)
Discovery [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									0
Payments of Ordinary Dividends, Noncontrolling Interest									0	0	0
Payments for investments, net									0		0
Net income									(337)	1,194	1,034
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(159)	1,065	807
Comprehensive income attributable to noncontrolling interests										0	0
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(1)	(23)	23
Comprehensive income attributable to Discovery Communications Inc.									(160)	1,042	830
DCH [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									0
Payments of Ordinary Dividends, Noncontrolling Interest									0	0	0
Payments for investments, net									0		0
Net income									(288)	1,203	1,044
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(110)	1,074	817
Comprehensive income attributable to noncontrolling interests										0	0
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(1)	(23)	23
Comprehensive income attributable to Discovery Communications Inc.									(111)	1,051	840
DCL [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									(40)
Payments of Ordinary Dividends, Noncontrolling Interest									0	0	0
Payments for investments, net									(45)		(10)
Net income									(288)	1,203	1,044
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(110)	1,074	817
Comprehensive income attributable to noncontrolling interests										0	0
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(1)	(23)	23
Comprehensive income attributable to Discovery Communications Inc.									(111)	1,051	840
Non-Guarantor Subsidiaries Of DCL [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									0
Payments of Ordinary Dividends, Noncontrolling Interest									30	22	42
Payments for investments, net									(399)		(262)
Net income									(517)	626	519
Currency translation adjustments									186	(190)	(199)
Market value adjustments									15	38	(25)
Derivative adjustments									(9)	22	(3)
Comprehensive income									(325)	496	292
Comprehensive income attributable to noncontrolling interests										0	0
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(1)	(23)	23
Comprehensive income attributable to Discovery Communications Inc.									(326)	473	315
Other Non - Guarantor Subsidiaries Of Discovery [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									0
Payments of Ordinary Dividends, Noncontrolling Interest									0	0	0
Payments for investments, net									0		0
Net income									(192)	802	696
Currency translation adjustments									122	(127)	(134)
Market value adjustments									10	25	(17)
Derivative adjustments									(13)	16	(1)
Comprehensive income									(73)	716	544
Comprehensive income attributable to noncontrolling interests										0	0
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(1)	(15)	15
Comprehensive income attributable to Discovery Communications Inc.									(74)	701	559
Discovery and Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Payments of Financing Costs									(40)
Payments of Ordinary Dividends, Noncontrolling Interest									30	22	42
Payments for investments, net									(444)		(272)
Net income									(313)	1,218	1,048
Currency translation adjustments									183	(191)	(201)
Market value adjustments									15	38	(25)
Derivative adjustments									(20)	24	(1)
Comprehensive income									(135)	1,089	821
Comprehensive income attributable to noncontrolling interests										(1)	(1)
Comprehensive (income) loss attributable to redeemable noncontrolling interests									(25)	(23)	10
Comprehensive income attributable to Discovery Communications Inc.									$ (160)	$ 1,065	$ 830

Condensed Consolidating Fina145

Condensed Consolidating Financial Statements (Condensed Consolidating Statement Of Cash Flows) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities
Cash provided by operating activities	$ 1,629	$ 1,380	$ 1,294
Investing Activities
Payments for (Proceeds from) Investments	444	272
Payments for investments, net			(272)
Purchases of property and equipment	(135)	(88)	(103)
Business acquisitions, net of cash acquired	(60)	0	(80)
Payments for derivative instruments, net	(101)	0	(9)
Proceeds from dispositions, net of cash disposed	29	19	61
Distributions from equity method investees, net	77	87	87
Other investing activities, net	1	(2)	15
Cash used in investing activities	(633)	(256)	(301)
Financing Activities
Commercial paper (repayments) borrowings, net	(48)	(45)	(136)
Borrowings under revolving credit facility	350	613	1,016
Principal repayments of revolving credit facility	(475)	(835)	(265)
Borrowings from debt, net of discount	7,488	498	936
Principal repayments of debt	(650)	0	(854)
Principal repayments of capital lease obligations	(33)	(28)	(27)
Repurchases of stock and stock settlements of common stock repurchase contracts	(603)	(1,374)	(951)
Cash proceeds from settlement of common stock repurchase contract	58	(57)
Prepayments for outstanding common stock repurchase contracts			0
Purchase of redeemable noncontrolling interests	0	0	(548)
Payments to redeemable noncontrolling interests	(30)	(22)	(42)
Equity-based plan proceeds, net	16	39	(6)
Hedge of borrowings from debt instruments	0	40	(29)
Other financing activities, net	(82)	(13)	(13)
Cash used in financing activities	5,951	(1,184)	(919)
Effect of exchange rate changes on cash and cash equivalents	62	(30)	(51)
Net change in cash and cash equivalents	7,009	(90)	23
Cash and cash equivalents, beginning of period	300	390	367
Cash and cash equivalents, end of period	7,309	300	390
Reclassifications and Eliminations [Member]
Operating Activities
Cash provided by operating activities	0	0	0
Investing Activities
Payments for (Proceeds from) Investments		0
Payments for investments, net	0		0
Purchases of property and equipment	0	0	0
Business acquisitions, net of cash acquired	0		0
Payments for Hedge, Investing Activities			0
Payments for derivative instruments, net	0
Proceeds from dispositions, net of cash disposed	0	0	0
Distributions from equity method investees, net	0	0	0
Investments in equity method investees, net			(37)
Inter-company distributions	(42)	(30)
Other investing activities, net	0	0	0
Cash used in investing activities	(42)	(30)	(37)
Financing Activities
Commercial paper (repayments) borrowings, net	0	0	0
Borrowings under revolving credit facility	0	0	0
Principal repayments of revolving credit facility	0	0	0
Borrowings from debt, net of discount	0	0	0
Principal repayments of debt	0		0
Principal repayments of capital lease obligations	0	0	0
Repurchases of stock and stock settlements of common stock repurchase contracts	0	0	0
Payments for Repurchase of Common Stock			0
Cash proceeds from settlement of common stock repurchase contract	0
Purchase of redeemable noncontrolling interests		0
Payments to redeemable noncontrolling interests	0	0	0
Equity-based plan proceeds, net	0	0	0
Inter-company contributions and other financing activities, net			0
Hedge of borrowings from debt instruments		0	0
Inter-company distributions, financing activities	(42)	30	37
Other financing activities, net	0	0
Cash used in financing activities	42	30	37
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net change in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	0	0	0
Discovery [Member]
Operating Activities
Cash provided by operating activities	(3)	(20)	(122)
Investing Activities
Payments for (Proceeds from) Investments		0
Payments for investments, net	0		0
Purchases of property and equipment	0	0	0
Business acquisitions, net of cash acquired	0		0
Payments for Hedge, Investing Activities			0
Payments for derivative instruments, net	0
Proceeds from dispositions, net of cash disposed	0	0	0
Distributions from equity method investees, net	0	0	0
Investments in equity method investees, net			0
Inter-company distributions	0	0
Other investing activities, net	0	0	0
Cash used in investing activities	0	0	0
Financing Activities
Commercial paper (repayments) borrowings, net	0	0	0
Borrowings under revolving credit facility	0	0	0
Principal repayments of revolving credit facility	0	0	0
Borrowings from debt, net of discount	0	0	0
Principal repayments of debt	0		0
Principal repayments of capital lease obligations	0	0	0
Repurchases of stock and stock settlements of common stock repurchase contracts	(603)	(1,374)	(951)
Payments for Repurchase of Common Stock			0
Cash proceeds from settlement of common stock repurchase contract	58
Purchase of redeemable noncontrolling interests		(57)
Payments to redeemable noncontrolling interests	0	0	0
Equity-based plan proceeds, net	16	39	(6)
Inter-company contributions and other financing activities, net			1,079
Hedge of borrowings from debt instruments		0	0
Inter-company distributions, financing activities	0	0	0
Other financing activities, net	532	(1,412)
Cash used in financing activities	3	20	122
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net change in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	0	0	0
DCH [Member]
Operating Activities
Cash provided by operating activities	3	(9)	(15)
Investing Activities
Payments for (Proceeds from) Investments		0
Payments for investments, net	0		0
Purchases of property and equipment	0	0	0
Business acquisitions, net of cash acquired	0		0
Payments for Hedge, Investing Activities			0
Payments for derivative instruments, net	0
Proceeds from dispositions, net of cash disposed	0	0	0
Distributions from equity method investees, net	0	0	0
Investments in equity method investees, net			0
Inter-company distributions	0	0
Other investing activities, net	0	0	0
Cash used in investing activities	0	0	0
Financing Activities
Commercial paper (repayments) borrowings, net	0	0	0
Borrowings under revolving credit facility	0	0	0
Principal repayments of revolving credit facility	0	0	0
Borrowings from debt, net of discount	0	0	0
Principal repayments of debt	0		0
Principal repayments of capital lease obligations	0	0	0
Repurchases of stock and stock settlements of common stock repurchase contracts	0	0	0
Payments for Repurchase of Common Stock			0
Cash proceeds from settlement of common stock repurchase contract	0
Purchase of redeemable noncontrolling interests		0
Payments to redeemable noncontrolling interests	0	0	0
Equity-based plan proceeds, net	0	0	0
Inter-company contributions and other financing activities, net			15
Hedge of borrowings from debt instruments		0	0
Inter-company distributions, financing activities	0	0	0
Other financing activities, net	(3)	(9)
Cash used in financing activities	(3)	9	15
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net change in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	0	0	0
DCL [Member]
Operating Activities
Cash provided by operating activities	476	249	427
Investing Activities
Payments for (Proceeds from) Investments		124
Payments for investments, net	(45)		(10)
Purchases of property and equipment	(43)	(18)	(17)
Business acquisitions, net of cash acquired	0		0
Payments for Hedge, Investing Activities			(11)
Payments for derivative instruments, net	(111)
Proceeds from dispositions, net of cash disposed	0	0	0
Distributions from equity method investees, net	0	0	0
Investments in equity method investees, net			37
Inter-company distributions	42	30
Other investing activities, net	(1)	0	0
Cash used in investing activities	(158)	(112)	(1)
Financing Activities
Commercial paper (repayments) borrowings, net	(48)	(45)	(136)
Borrowings under revolving credit facility	350	350	0
Principal repayments of revolving credit facility	(475)	(225)	(13)
Borrowings from debt, net of discount	7,488	498	936
Principal repayments of debt	(650)		(854)
Principal repayments of capital lease obligations	(7)	(5)	5
Repurchases of stock and stock settlements of common stock repurchase contracts	0	0	0
Payments for Repurchase of Common Stock			0
Cash proceeds from settlement of common stock repurchase contract	0
Purchase of redeemable noncontrolling interests		0
Payments to redeemable noncontrolling interests	0	0	0
Equity-based plan proceeds, net	0	0	0
Inter-company contributions and other financing activities, net			(330)
Hedge of borrowings from debt instruments		40	(29)
Inter-company distributions, financing activities	0	0	0
Other financing activities, net	(156)	733
Cash used in financing activities	6,462	(120)	(431)
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net change in cash and cash equivalents	6,780	17	(5)
Cash and cash equivalents, beginning of period	20	3	8
Cash and cash equivalents, end of period	6,800	20	3
Non-Guarantor Subsidiaries Of DCL [Member]
Operating Activities
Cash provided by operating activities	1,153	1,160	1,004
Investing Activities
Payments for (Proceeds from) Investments		148
Payments for investments, net	(399)		(262)
Purchases of property and equipment	(92)	(70)	(86)
Business acquisitions, net of cash acquired	(60)		(80)
Payments for Hedge, Investing Activities			2
Payments for derivative instruments, net	10
Proceeds from dispositions, net of cash disposed	29	19	61
Distributions from equity method investees, net	77	87	87
Investments in equity method investees, net			0
Inter-company distributions	0	0
Other investing activities, net	2	(2)	15
Cash used in investing activities	(433)	(114)	(263)
Financing Activities
Commercial paper (repayments) borrowings, net	0	0	0
Borrowings under revolving credit facility	0	263	1,016
Principal repayments of revolving credit facility	0	(610)	(252)
Borrowings from debt, net of discount	0	0	0
Principal repayments of debt	0		0
Principal repayments of capital lease obligations	(26)	(23)	22
Repurchases of stock and stock settlements of common stock repurchase contracts	0	0	0
Payments for Repurchase of Common Stock			548
Cash proceeds from settlement of common stock repurchase contract	0
Purchase of redeemable noncontrolling interests		0
Payments to redeemable noncontrolling interests	(30)	(22)	(42)
Equity-based plan proceeds, net	0	0	0
Inter-company contributions and other financing activities, net			(777)
Hedge of borrowings from debt instruments		0	0
Inter-company distributions, financing activities	42	(30)	(37)
Other financing activities, net	(455)	701
Cash used in financing activities	(553)	(1,123)	(662)
Effect of exchange rate changes on cash and cash equivalents	62	(30)	(51)
Net change in cash and cash equivalents	229	(107)	28
Cash and cash equivalents, beginning of period	280	387	359
Cash and cash equivalents, end of period	509	280	387
Other Non - Guarantor Subsidiaries Of Discovery [Member]
Operating Activities
Cash provided by operating activities	0	0	0
Investing Activities
Payments for (Proceeds from) Investments		0
Payments for investments, net	0		0
Purchases of property and equipment	0	0	0
Business acquisitions, net of cash acquired	0		0
Payments for Hedge, Investing Activities			0
Payments for derivative instruments, net	0
Proceeds from dispositions, net of cash disposed	0	0	0
Distributions from equity method investees, net	0	0	0
Investments in equity method investees, net			0
Inter-company distributions	0	0
Other investing activities, net	0	0	0
Cash used in investing activities	0	0	0
Financing Activities
Commercial paper (repayments) borrowings, net	0	0	0
Borrowings under revolving credit facility	0	0	0
Principal repayments of revolving credit facility	0	0	0
Borrowings from debt, net of discount	0	0	0
Principal repayments of debt	0		0
Principal repayments of capital lease obligations	0	0	0
Repurchases of stock and stock settlements of common stock repurchase contracts	0	0	0
Payments for Repurchase of Common Stock			0
Cash proceeds from settlement of common stock repurchase contract	0
Purchase of redeemable noncontrolling interests		0
Payments to redeemable noncontrolling interests	0	0	0
Equity-based plan proceeds, net	0	0	0
Inter-company contributions and other financing activities, net			0
Hedge of borrowings from debt instruments		0	0
Inter-company distributions, financing activities	0	0	0
Other financing activities, net	0	0
Cash used in financing activities	0	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net change in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	0	0	0
Discovery and Subsidiaries [Member]
Operating Activities
Cash provided by operating activities	1,629	1,380	1,294
Investing Activities
Payments for (Proceeds from) Investments		272
Payments for investments, net	(444)		(272)
Purchases of property and equipment	(135)	(88)	(103)
Business acquisitions, net of cash acquired	(60)
Payments for Hedge, Investing Activities			(9)
Payments for derivative instruments, net	(101)
Proceeds from dispositions, net of cash disposed	29	19	61
Distributions from equity method investees, net	77	87	87
Investments in equity method investees, net			0
Inter-company distributions	0	0
Other investing activities, net	1	(2)	15
Cash used in investing activities	(633)	(256)	(301)
Financing Activities
Commercial paper (repayments) borrowings, net	(48)	(45)	(136)
Borrowings under revolving credit facility	350	613	1,016
Principal repayments of revolving credit facility	(475)	(835)	(265)
Borrowings from debt, net of discount	7,488	498	936
Principal repayments of debt	(650)		(854)
Principal repayments of capital lease obligations	(33)	(28)	27
Repurchases of stock and stock settlements of common stock repurchase contracts	(603)	(1,374)	(951)
Payments for Repurchase of Common Stock			548
Cash proceeds from settlement of common stock repurchase contract	58
Purchase of redeemable noncontrolling interests		(57)
Payments to redeemable noncontrolling interests	(30)	(22)	(42)
Equity-based plan proceeds, net	16	39	(6)
Inter-company contributions and other financing activities, net			(13)
Hedge of borrowings from debt instruments		40	(29)
Inter-company distributions, financing activities	0	0	0
Other financing activities, net	(82)	13
Cash used in financing activities	5,951	(1,184)	(919)
Effect of exchange rate changes on cash and cash equivalents	62	(30)	(51)
Net change in cash and cash equivalents	7,009	(90)	23
Cash and cash equivalents, beginning of period	300	390	367
Cash and cash equivalents, end of period	$ 7,309	$ 300	$ 390