Condensed Consolidating Financial Statements (Balance Sheet) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Cash and cash equivalents	$ 196	$ 322
Receivables, net	3,685	4,041
Programming and other inventory	1,964	1,988
Prepaid expenses and other current assets	428	401
Total current assets	6,273	6,752
Property and equipment	2,942	2,926
Less accumulated depreciation and amortization	1,771	1,717
Net property and equipment	1,171	1,209
Programming and other inventory	4,861	3,883
Goodwill	5,064	4,920
Intangible assets	2,655	2,638
Operating lease assets	1,001	0
Investments in consolidated subsidiaries	0	0
Deferred income tax assets, net	779	29
Other assets	2,672	2,395
Assets held for sale	0	33
Intercompany	0	0
Total Assets	24,476	21,859
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	308	201
Participants’ share and royalties payable	1,201	1,177
Accrued programming and production costs	635	704
Commercial paper	50	674
Accrued expenses and other current liabilities	1,928	1,817
Total current liabilities	4,122	4,573
Long-term debt	9,359	9,465
Noncurrent operating lease liabilities	948	0
Other liabilities	4,995	5,017
Intercompany	0	0
Stockholders’ Equity:
Preferred stock	0	0
Common stock	1	1
Additional paid-in capital	43,510	43,637
Retained earnings (accumulated deficit)	(14,683)	(17,201)
Accumulated other comprehensive income (loss)	(918)	(775)	$ (634)	$ (662)
Stockholders' equity including treasury stock	27,910	25,662
Less treasury stock, at cost	22,858	22,858
Total Stockholders’ Equity	5,052	2,804	$ 2,514
Total Liabilities and Stockholders’ Equity	24,476	21,859
Eliminations [Member]
ASSETS
Cash and cash equivalents	0	0
Receivables, net	0	0
Programming and other inventory	0	0
Prepaid expenses and other current assets	(36)	(36)
Total current assets	(36)	(36)
Property and equipment	0	0
Less accumulated depreciation and amortization	0	0
Net property and equipment	0	0
Programming and other inventory	0	0
Goodwill	0	0
Intangible assets	0	0
Operating lease assets	0
Investments in consolidated subsidiaries	(67,995)	(64,501)
Deferred income tax assets, net	0	0
Other assets	0	0
Assets held for sale		0
Intercompany	(33,740)	(32,212)
Total Assets	(101,771)	(96,749)
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	0	0
Participants’ share and royalties payable	0	0
Accrued programming and production costs	0	0
Commercial paper	0	0
Accrued expenses and other current liabilities	(36)	(36)
Total current liabilities	(36)	(36)
Long-term debt	0	0
Noncurrent operating lease liabilities	0
Other liabilities	0	0
Intercompany	(33,740)	(32,212)
Stockholders’ Equity:
Preferred stock	(126)	(126)
Common stock	(713)	(713)
Additional paid-in capital	(60,894)	(60,894)
Retained earnings (accumulated deficit)	(11,342)	(7,833)
Accumulated other comprehensive income (loss)	(51)	(66)
Stockholders' equity including treasury stock	(73,126)	(69,632)
Less treasury stock, at cost	(5,131)	(5,131)
Total Stockholders’ Equity	(67,995)	(64,501)
Total Liabilities and Stockholders’ Equity	(101,771)	(96,749)
CBS Corp. [Member]
ASSETS
Cash and cash equivalents	102	148
Receivables, net	20	27
Programming and other inventory	3	2
Prepaid expenses and other current assets	6	81
Total current assets	131	258
Property and equipment	31	31
Less accumulated depreciation and amortization	15	14
Net property and equipment	16	17
Programming and other inventory	5	5
Goodwill	98	98
Intangible assets	0	0
Operating lease assets	9
Investments in consolidated subsidiaries	50,434	47,600
Deferred income tax assets, net	0	0
Other assets	292	281
Assets held for sale		0
Intercompany	0	0
Total Assets	50,985	48,259
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	4	5
Participants’ share and royalties payable	0	0
Accrued programming and production costs	2	3
Commercial paper	50	674
Accrued expenses and other current liabilities	377	396
Total current liabilities	433	1,078
Long-term debt	9,290	9,388
Noncurrent operating lease liabilities	8
Other liabilities	2,568	2,777
Intercompany	33,634	32,212
Stockholders’ Equity:
Preferred stock	0	0
Common stock	1	1
Additional paid-in capital	43,510	43,637
Retained earnings (accumulated deficit)	(14,683)	(17,201)
Accumulated other comprehensive income (loss)	(918)	(775)
Stockholders' equity including treasury stock	27,910	25,662
Less treasury stock, at cost	22,858	22,858
Total Stockholders’ Equity	5,052	2,804
Total Liabilities and Stockholders’ Equity	50,985	48,259
CBS Operations Inc. [Member]
ASSETS
Cash and cash equivalents	0	0
Receivables, net	1	1
Programming and other inventory	1	2
Prepaid expenses and other current assets	39	46
Total current assets	41	49
Property and equipment	228	223
Less accumulated depreciation and amortization	198	184
Net property and equipment	30	39
Programming and other inventory	4	4
Goodwill	62	62
Intangible assets	0	0
Operating lease assets	106
Investments in consolidated subsidiaries	17,561	16,901
Deferred income tax assets, net	0	0
Other assets	0	0
Assets held for sale		0
Intercompany	0	526
Total Assets	17,804	17,581
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	34	31
Participants’ share and royalties payable	0	0
Accrued programming and production costs	2	2
Commercial paper	0	0
Accrued expenses and other current liabilities	334	308
Total current liabilities	370	341
Long-term debt	0	0
Noncurrent operating lease liabilities	100
Other liabilities	208	212
Intercompany	106	0
Stockholders’ Equity:
Preferred stock	0	0
Common stock	123	123
Additional paid-in capital	0	0
Retained earnings (accumulated deficit)	17,200	17,214
Accumulated other comprehensive income (loss)	28	22
Stockholders' equity including treasury stock	17,351	17,359
Less treasury stock, at cost	331	331
Total Stockholders’ Equity	17,020	17,028
Total Liabilities and Stockholders’ Equity	17,804	17,581
Non-Guarantor Affiliates [Member]
ASSETS
Cash and cash equivalents	94	174
Receivables, net	3,664	4,013
Programming and other inventory	1,960	1,984
Prepaid expenses and other current assets	419	310
Total current assets	6,137	6,481
Property and equipment	2,683	2,672
Less accumulated depreciation and amortization	1,558	1,519
Net property and equipment	1,125	1,153
Programming and other inventory	4,852	3,874
Goodwill	4,904	4,760
Intangible assets	2,655	2,638
Operating lease assets	886
Investments in consolidated subsidiaries	0	0
Deferred income tax assets, net	779	29
Other assets	2,380	2,114
Assets held for sale		33
Intercompany	33,740	31,686
Total Assets	57,458	52,768
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	270	165
Participants’ share and royalties payable	1,201	1,177
Accrued programming and production costs	631	699
Commercial paper	0	0
Accrued expenses and other current liabilities	1,253	1,149
Total current liabilities	3,355	3,190
Long-term debt	69	77
Noncurrent operating lease liabilities	840
Other liabilities	2,219	2,028
Intercompany	0	0
Stockholders’ Equity:
Preferred stock	126	126
Common stock	590	590
Additional paid-in capital	60,894	60,894
Retained earnings (accumulated deficit)	(5,858)	(9,381)
Accumulated other comprehensive income (loss)	23	44
Stockholders' equity including treasury stock	55,775	52,273
Less treasury stock, at cost	4,800	4,800
Total Stockholders’ Equity	50,975	47,473
Total Liabilities and Stockholders’ Equity	$ 57,458	$ 52,768