Fair Value Measurements (Schedule Of Assets And Liabilities Measured On Recurring Basis) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	$ 1,066	$ 262
Liabilities	235	233
Cash Equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	5	10
Treasury securities	500
Equity securities	59
Prepaid expenses and other current assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	250
Equity securities	13	11
Company-owned life insurance contracts	3	4
Other noncurrent assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities	190	192
Company-owned life insurance contracts	46	45
Accrued liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	26	24
Other noncurrent liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	209	209
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	703	203
Liabilities	235	233
Level 1 \| Cash Equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	0	0
Treasury securities	500
Equity securities	0
Level 1 \| Prepaid expenses and other current assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	0
Equity securities	13	11
Company-owned life insurance contracts	0	0
Level 1 \| Other noncurrent assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities	190	192
Company-owned life insurance contracts	0	0
Level 1 \| Accrued liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	26	24
Level 1 \| Other noncurrent liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	209	209
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	363	59
Liabilities	0	0
Level 2 \| Cash Equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	5	10
Treasury securities	0
Equity securities	59
Level 2 \| Prepaid expenses and other current assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	250
Equity securities	0	0
Company-owned life insurance contracts	3	4
Level 2 \| Other noncurrent assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities	0	0
Company-owned life insurance contracts	46	45
Level 2 \| Accrued liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	0	0
Level 2 \| Other noncurrent liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	0	0
Liabilities	0	0
Level 3 \| Cash Equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	0	0
Treasury securities	0
Equity securities	0
Level 3 \| Prepaid expenses and other current assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	0
Equity securities	0	0
Company-owned life insurance contracts	0	0
Level 3 \| Other noncurrent assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities	0	0
Company-owned life insurance contracts	0	0
Level 3 \| Accrued liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	0	0
Level 3 \| Other noncurrent liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation plan	$ 0	$ 0

CertificatesOfDepositRestrictedFairValueDisclosure

No definition available.

Name:	disca_CertificatesOfDepositRestrictedFairValueDisclosure
Namespace Prefix:	disca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Treasury Securities

+ References

No definition available.

+ Details

Name:	disca_TreasurySecurities
Namespace Prefix:	disca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_AssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ References

No definition available.

+ Details

Name:	us-gaap_CashSurrenderValueFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements. Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredCompensationCashbasedArrangementsLiabilityCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of financial and nonfinancial obligations.

+ References

+ Details

Name:	us-gaap_LiabilitiesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

Name:	us-gaap_TradingSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_CashAndCashEquivalentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_AccruedLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: