Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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+ References

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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Debt (Commercial Paper Narrative) (Details) - USD ($)	12 Months Ended
Debt (Commercial Paper Narrative) (Details) - USD ($)	Dec. 31, 2019	Sep. 30, 2020	Jan. 31, 2020
Line of Credit Facility [Line Items]
Commercial paper	$ 699,000,000	$ 0
Commercial Paper [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity under credit facility	$ 2,500,000,000		$ 3,500,000,000
Debt maturity, less than	90 days
Weighted average interest rate	2.07%
Revolving Credit Facility [Member] \| ViacomCBS Credit Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity under credit facility			$ 3,500,000,000