Condensed Consolidating Financial Statements (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Condensed Consolidating Statement Of Operations [Abstract]
Revenues	$ 3,343,000,000	$ 3,588,000,000
Cost and expenses:
Operating	2,074,000,000	2,272,000,000
Selling, general and administrative	510,000,000	503,000,000
Depreciation and amortization	55,000,000	57,000,000
Other operating items, net	0	(9,000,000)
Total costs and expenses	2,639,000,000	2,823,000,000
Operating income (loss)	704,000,000	765,000,000
Interest (expense) income, net	(96,000,000)	(93,000,000)
Other items, net	1,000,000	(3,000,000)
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	609,000,000	669,000,000
Benefit (provision) for income taxes	(138,000,000)	(206,000,000)
Equity in earnings (loss) of investee companies, net of tax	(17,000,000)	(21,000,000)
Net earnings (loss) from continuing operations	454,000,000	442,000,000
Net earnings (loss) from discontinued operations, net of tax (Note 3)	(706,000,000)	31,000,000
Net earnings (loss)	(252,000,000)	473,000,000
Total comprehensive income (loss)	(238,000,000)	484,000,000
Assets [Abstract]
Cash and cash equivalents	163,000,000		$ 598,000,000
Receivables, net	3,478,000,000		3,314,000,000
Programming and other inventory (Note 4)	1,201,000,000		1,427,000,000
Prepaid expenses and other current assets	520,000,000		419,000,000
Current assets of discontinued operations	258,000,000		305,000,000
Total current assets	5,620,000,000		6,063,000,000
Property and equipment	2,943,000,000		2,935,000,000
Less accumulated depreciation and amortization	1,723,000,000		1,694,000,000
Net property and equipment	1,220,000,000		1,241,000,000
Programming and other inventory (Note 4)	2,546,000,000		2,439,000,000
Goodwill	4,889,000,000		4,864,000,000
Intangible assets	2,631,000,000		2,633,000,000
Investments in consolidated subsidiaries	0		0
Other assets	2,539,000,000		2,707,000,000
Intercompany	0		0
Assets of discontinued operations	3,577,000,000		4,291,000,000
Total Assets	23,022,000,000		24,238,000,000
Liabilities and Stockholders' Equity [Abstract]
Accounts payable	158,000,000		148,000,000
Participants' share and royalties payable	1,022,000,000		1,024,000,000
Program rights	477,000,000		290,000,000
Commercial paper	30,000,000		450,000,000
Current portion of long-term debt (Note 6)	23,000,000		23,000,000
Accrued expenses and other current liabilities	1,563,000,000		1,618,000,000
Current liabilities of discontinued operations	151,000,000		155,000,000
Total current liabilities	3,424,000,000		3,708,000,000
Long-term debt (Note 6)	8,900,000,000		8,902,000,000
Other liabilities	5,359,000,000		5,488,000,000
Liabilities of discontinued operations	2,454,000,000		2,451,000,000
Intercompany	0		0
Stockholders' Equity [Abstract]
Preferred stock	0		0
Common stock	1,000,000		1,000,000
Additional paid-in capital	43,847,000,000		43,913,000,000
Retained earnings (accumulated deficit)	(19,509,000,000)		(19,257,000,000)
Accumulated other comprehensive income (loss)	(753,000,000)	(759,000,000)	(767,000,000)	$ (770,000,000)
Stockholders' equity including treasury stock	23,586,000,000		23,890,000,000
Less treasury stock, at cost	20,701,000,000		20,201,000,000
Total Stockholders' Equity	2,885,000,000		3,689,000,000
Total Liabilities and Stockholders' Equity	23,022,000,000		24,238,000,000
Condensed Consolidating Statement Of Cash Flows [Abstract]
Net cash flow provided by (used for) operating activities	719,000,000	1,028,000,000
Investing Activities
Acquisitions	(21,000,000)	(50,000,000)
Capital expenditures	(27,000,000)	(34,000,000)
Investments in and advances to investee companies	(49,000,000)	(32,000,000)
Proceeds from dispositions	1,000,000	21,000,000
Other investing activities	14,000,000	(7,000,000)
Net cash flow provided by (used for) investing activities from continuing operations	(82,000,000)	(102,000,000)
Net cash flow provided by (used for) investing activities from discontinued operations	(7,000,000)	4,000,000
Net cash flow provided by (used for) investing activities	(89,000,000)	(98,000,000)
Financing Activities
Proceeds from (repayments of) short-term debt borrowings, net	(420,000,000)	0
Repayment of senior debentures	0	(200,000,000)
Repayment of debt borrowings of CBS Radio	(3,000,000)	0
Payment of capital lease obligations	(4,000,000)	(4,000,000)
Payment of contingent consideration	(7,000,000)	0
Dividends	(77,000,000)	(73,000,000)
Purchase of Company common stock	(531,000,000)	(533,000,000)
Payment of payroll taxes in lieu of issuing shares for stock-based compensation	(76,000,000)	(46,000,000)
Proceeds from exercise of stock options	36,000,000	6,000,000
Excess tax benefit from stock-based compensation	0	8,000,000
Increase (decrease) in intercompany payables	0	0
Net cash flow provided by (used for) financing activities	(1,082,000,000)	(842,000,000)
Net increase (decrease) in cash and cash equivalents	(452,000,000)	88,000,000
Cash and cash equivalents, including discontinued operations, at beginning of period	622,000,000	323,000,000
Cash and cash equivalents, including discontinued operations, at end of period	170,000,000	411,000,000
Cash and cash equivalents of discontinued operations	7,000,000	2,000,000	24,000,000	$ 6,000,000
Eliminations [Member]
Condensed Consolidating Statement Of Operations [Abstract]
Revenues	0	0
Cost and expenses:
Operating	0	0
Selling, general and administrative	0	0
Depreciation and amortization	0	0
Other operating items, net		0
Total costs and expenses	0	0
Operating income (loss)	0	0
Interest (expense) income, net	0	0
Other items, net	0	0
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	0	0
Benefit (provision) for income taxes	0	0
Equity in earnings (loss) of investee companies, net of tax	(189,000,000)	(813,000,000)
Net earnings (loss) from continuing operations	(189,000,000)	(813,000,000)
Net earnings (loss) from discontinued operations, net of tax (Note 3)	0	0
Net earnings (loss)	(189,000,000)	(813,000,000)
Total comprehensive income (loss)	(193,000,000)	(819,000,000)
Assets [Abstract]
Cash and cash equivalents	0		0
Receivables, net	0		0
Programming and other inventory (Note 4)	0		0
Prepaid expenses and other current assets	(34,000,000)		(35,000,000)
Current assets of discontinued operations	0		0
Total current assets	(34,000,000)		(35,000,000)
Property and equipment	0		0
Less accumulated depreciation and amortization	0		0
Net property and equipment	0		0
Programming and other inventory (Note 4)	0		0
Goodwill	0		0
Intangible assets	0		0
Investments in consolidated subsidiaries	(58,519,000,000)		(58,326,000,000)
Other assets	0		0
Intercompany	(29,622,000,000)		(28,761,000,000)
Assets of discontinued operations	0		0
Total Assets	(88,175,000,000)		(87,122,000,000)
Liabilities and Stockholders' Equity [Abstract]
Accounts payable	0		0
Participants' share and royalties payable	0		0
Program rights	0		0
Commercial paper	0		0
Current portion of long-term debt (Note 6)	0		0
Accrued expenses and other current liabilities	(34,000,000)		(35,000,000)
Current liabilities of discontinued operations	0		0
Total current liabilities	(34,000,000)		(35,000,000)
Long-term debt (Note 6)	0		0
Other liabilities	0		0
Liabilities of discontinued operations	0		0
Intercompany	(29,622,000,000)		(28,761,000,000)
Stockholders' Equity [Abstract]
Preferred stock	(126,000,000)		(126,000,000)
Common stock	(713,000,000)		(713,000,000)
Additional paid-in capital	(60,894,000,000)		(60,894,000,000)
Retained earnings (accumulated deficit)	(1,834,000,000)		(1,645,000,000)
Accumulated other comprehensive income (loss)	(83,000,000)		(79,000,000)
Stockholders' equity including treasury stock	(63,650,000,000)		(63,457,000,000)
Less treasury stock, at cost	(5,131,000,000)		(5,131,000,000)
Total Stockholders' Equity	(58,519,000,000)		(58,326,000,000)
Total Liabilities and Stockholders' Equity	(88,175,000,000)		(87,122,000,000)
Condensed Consolidating Statement Of Cash Flows [Abstract]
Net cash flow provided by (used for) operating activities	0	0
Investing Activities
Acquisitions	0	0
Capital expenditures	0	0
Investments in and advances to investee companies	0	0
Proceeds from dispositions	0	0
Other investing activities	0	0
Net cash flow provided by (used for) investing activities from continuing operations	0	0
Net cash flow provided by (used for) investing activities from discontinued operations	0	0
Net cash flow provided by (used for) investing activities	0	0
Financing Activities
Proceeds from (repayments of) short-term debt borrowings, net	0
Repayment of senior debentures		0
Repayment of debt borrowings of CBS Radio	0
Payment of capital lease obligations	0	0
Payment of contingent consideration	0
Dividends	0	0
Purchase of Company common stock	0	0
Payment of payroll taxes in lieu of issuing shares for stock-based compensation	0	0
Proceeds from exercise of stock options	0	0
Excess tax benefit from stock-based compensation		0
Increase (decrease) in intercompany payables	0	0
Net cash flow provided by (used for) financing activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, including discontinued operations, at beginning of period	0	0
Cash and cash equivalents, including discontinued operations, at end of period	0	0
CBS Corp. [Member]
Condensed Consolidating Statement Of Operations [Abstract]
Revenues	42,000,000	47,000,000
Cost and expenses:
Operating	24,000,000	17,000,000
Selling, general and administrative	20,000,000	21,000,000
Depreciation and amortization	1,000,000	1,000,000
Other operating items, net		0
Total costs and expenses	45,000,000	39,000,000
Operating income (loss)	(3,000,000)	8,000,000
Interest (expense) income, net	(122,000,000)	(124,000,000)
Other items, net	0	(1,000,000)
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	(125,000,000)	(117,000,000)
Benefit (provision) for income taxes	38,000,000	37,000,000
Equity in earnings (loss) of investee companies, net of tax	(165,000,000)	553,000,000
Net earnings (loss) from continuing operations	(252,000,000)	473,000,000
Net earnings (loss) from discontinued operations, net of tax (Note 3)	0	0
Net earnings (loss)	(252,000,000)	473,000,000
Total comprehensive income (loss)	(238,000,000)	484,000,000
Assets [Abstract]
Cash and cash equivalents	44,000,000		321,000,000
Receivables, net	25,000,000		27,000,000
Programming and other inventory (Note 4)	4,000,000		3,000,000
Prepaid expenses and other current assets	16,000,000		102,000,000
Current assets of discontinued operations	0		0
Total current assets	89,000,000		453,000,000
Property and equipment	48,000,000		47,000,000
Less accumulated depreciation and amortization	26,000,000		25,000,000
Net property and equipment	22,000,000		22,000,000
Programming and other inventory (Note 4)	4,000,000		5,000,000
Goodwill	98,000,000		98,000,000
Intangible assets	0		0
Investments in consolidated subsidiaries	44,312,000,000		44,473,000,000
Other assets	150,000,000		150,000,000
Intercompany	0		0
Assets of discontinued operations	0		0
Total Assets	44,675,000,000		45,201,000,000
Liabilities and Stockholders' Equity [Abstract]
Accounts payable	1,000,000		1,000,000
Participants' share and royalties payable	0		0
Program rights	4,000,000		4,000,000
Commercial paper	30,000,000		450,000,000
Current portion of long-term debt (Note 6)	6,000,000		6,000,000
Accrued expenses and other current liabilities	391,000,000		421,000,000
Current liabilities of discontinued operations	0		0
Total current liabilities	432,000,000		882,000,000
Long-term debt (Note 6)	8,799,000,000		8,798,000,000
Other liabilities	2,937,000,000		3,071,000,000
Liabilities of discontinued operations	0		0
Intercompany	29,622,000,000		28,761,000,000
Stockholders' Equity [Abstract]
Preferred stock	0		0
Common stock	1,000,000		1,000,000
Additional paid-in capital	43,847,000,000		43,913,000,000
Retained earnings (accumulated deficit)	(19,509,000,000)		(19,257,000,000)
Accumulated other comprehensive income (loss)	(753,000,000)		(767,000,000)
Stockholders' equity including treasury stock	23,586,000,000		23,890,000,000
Less treasury stock, at cost	20,701,000,000		20,201,000,000
Total Stockholders' Equity	2,885,000,000		3,689,000,000
Total Liabilities and Stockholders' Equity	44,675,000,000		45,201,000,000
Condensed Consolidating Statement Of Cash Flows [Abstract]
Net cash flow provided by (used for) operating activities	(256,000,000)	(157,000,000)
Investing Activities
Acquisitions	0	0
Capital expenditures	0	0
Investments in and advances to investee companies	0	0
Proceeds from dispositions	0	(2,000,000)
Other investing activities	14,000,000	(7,000,000)
Net cash flow provided by (used for) investing activities from continuing operations	14,000,000	(9,000,000)
Net cash flow provided by (used for) investing activities from discontinued operations	0	0
Net cash flow provided by (used for) investing activities	14,000,000	(9,000,000)
Financing Activities
Proceeds from (repayments of) short-term debt borrowings, net	(420,000,000)
Repayment of senior debentures		(200,000,000)
Repayment of debt borrowings of CBS Radio	0
Payment of capital lease obligations	0	0
Payment of contingent consideration	0
Dividends	(77,000,000)	(73,000,000)
Purchase of Company common stock	(531,000,000)	(533,000,000)
Payment of payroll taxes in lieu of issuing shares for stock-based compensation	(76,000,000)	(46,000,000)
Proceeds from exercise of stock options	36,000,000	6,000,000
Excess tax benefit from stock-based compensation		8,000,000
Increase (decrease) in intercompany payables	1,033,000,000	907,000,000
Net cash flow provided by (used for) financing activities	(35,000,000)	69,000,000
Net increase (decrease) in cash and cash equivalents	(277,000,000)	(97,000,000)
Cash and cash equivalents, including discontinued operations, at beginning of period	321,000,000	267,000,000
Cash and cash equivalents, including discontinued operations, at end of period	44,000,000	170,000,000
CBS Operations Inc. [Member]
Condensed Consolidating Statement Of Operations [Abstract]
Revenues	3,000,000	3,000,000
Cost and expenses:
Operating	1,000,000	1,000,000
Selling, general and administrative	64,000,000	66,000,000
Depreciation and amortization	6,000,000	5,000,000
Other operating items, net		0
Total costs and expenses	71,000,000	72,000,000
Operating income (loss)	(68,000,000)	(69,000,000)
Interest (expense) income, net	(117,000,000)	(104,000,000)
Other items, net	(13,000,000)	(10,000,000)
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	(198,000,000)	(183,000,000)
Benefit (provision) for income taxes	60,000,000	59,000,000
Equity in earnings (loss) of investee companies, net of tax	354,000,000	260,000,000
Net earnings (loss) from continuing operations	216,000,000	136,000,000
Net earnings (loss) from discontinued operations, net of tax (Note 3)	0	0
Net earnings (loss)	216,000,000	136,000,000
Total comprehensive income (loss)	214,000,000	140,000,000
Assets [Abstract]
Cash and cash equivalents	0		0
Receivables, net	2,000,000		2,000,000
Programming and other inventory (Note 4)	3,000,000		3,000,000
Prepaid expenses and other current assets	39,000,000		55,000,000
Current assets of discontinued operations	0		0
Total current assets	44,000,000		60,000,000
Property and equipment	204,000,000		201,000,000
Less accumulated depreciation and amortization	146,000,000		140,000,000
Net property and equipment	58,000,000		61,000,000
Programming and other inventory (Note 4)	6,000,000		7,000,000
Goodwill	62,000,000		62,000,000
Intangible assets	0		0
Investments in consolidated subsidiaries	14,207,000,000		13,853,000,000
Other assets	8,000,000		8,000,000
Intercompany	1,571,000,000		1,785,000,000
Assets of discontinued operations	0		3,000,000
Total Assets	15,956,000,000		15,839,000,000
Liabilities and Stockholders' Equity [Abstract]
Accounts payable	1,000,000		3,000,000
Participants' share and royalties payable	0		0
Program rights	3,000,000		4,000,000
Commercial paper	0		0
Current portion of long-term debt (Note 6)	0		0
Accrued expenses and other current liabilities	192,000,000		284,000,000
Current liabilities of discontinued operations	0		0
Total current liabilities	196,000,000		291,000,000
Long-term debt (Note 6)	0		0
Other liabilities	242,000,000		244,000,000
Liabilities of discontinued operations	0		0
Intercompany	0		0
Stockholders' Equity [Abstract]
Preferred stock	0		0
Common stock	123,000,000		123,000,000
Additional paid-in capital	0		0
Retained earnings (accumulated deficit)	15,699,000,000		15,483,000,000
Accumulated other comprehensive income (loss)	27,000,000		29,000,000
Stockholders' equity including treasury stock	15,849,000,000		15,635,000,000
Less treasury stock, at cost	331,000,000		331,000,000
Total Stockholders' Equity	15,518,000,000		15,304,000,000
Total Liabilities and Stockholders' Equity	15,956,000,000		15,839,000,000
Condensed Consolidating Statement Of Cash Flows [Abstract]
Net cash flow provided by (used for) operating activities	(118,000,000)	(103,000,000)
Investing Activities
Acquisitions	0	0
Capital expenditures	(4,000,000)	(9,000,000)
Investments in and advances to investee companies	0	0
Proceeds from dispositions	0	0
Other investing activities	0	0
Net cash flow provided by (used for) investing activities from continuing operations	(4,000,000)	(9,000,000)
Net cash flow provided by (used for) investing activities from discontinued operations	(1,000,000)	0
Net cash flow provided by (used for) investing activities	(5,000,000)	(9,000,000)
Financing Activities
Proceeds from (repayments of) short-term debt borrowings, net	0
Repayment of senior debentures		0
Repayment of debt borrowings of CBS Radio	0
Payment of capital lease obligations	0	0
Payment of contingent consideration	0
Dividends	0	0
Purchase of Company common stock	0	0
Payment of payroll taxes in lieu of issuing shares for stock-based compensation	0	0
Proceeds from exercise of stock options	0	0
Excess tax benefit from stock-based compensation		0
Increase (decrease) in intercompany payables	123,000,000	112,000,000
Net cash flow provided by (used for) financing activities	123,000,000	112,000,000
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, including discontinued operations, at beginning of period	0	1,000,000
Cash and cash equivalents, including discontinued operations, at end of period	0	1,000,000
Non-Guarantor Affiliates [Member]
Condensed Consolidating Statement Of Operations [Abstract]
Revenues	3,298,000,000	3,538,000,000
Cost and expenses:
Operating	2,049,000,000	2,254,000,000
Selling, general and administrative	426,000,000	416,000,000
Depreciation and amortization	48,000,000	51,000,000
Other operating items, net		(9,000,000)
Total costs and expenses	2,523,000,000	2,712,000,000
Operating income (loss)	775,000,000	826,000,000
Interest (expense) income, net	143,000,000	135,000,000
Other items, net	14,000,000	8,000,000
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	932,000,000	969,000,000
Benefit (provision) for income taxes	(236,000,000)	(302,000,000)
Equity in earnings (loss) of investee companies, net of tax	(17,000,000)	(21,000,000)
Net earnings (loss) from continuing operations	679,000,000	646,000,000
Net earnings (loss) from discontinued operations, net of tax (Note 3)	(706,000,000)	31,000,000
Net earnings (loss)	(27,000,000)	677,000,000
Total comprehensive income (loss)	(21,000,000)	679,000,000
Assets [Abstract]
Cash and cash equivalents	119,000,000		277,000,000
Receivables, net	3,451,000,000		3,285,000,000
Programming and other inventory (Note 4)	1,194,000,000		1,421,000,000
Prepaid expenses and other current assets	499,000,000		297,000,000
Current assets of discontinued operations	258,000,000		305,000,000
Total current assets	5,521,000,000		5,585,000,000
Property and equipment	2,691,000,000		2,687,000,000
Less accumulated depreciation and amortization	1,551,000,000		1,529,000,000
Net property and equipment	1,140,000,000		1,158,000,000
Programming and other inventory (Note 4)	2,536,000,000		2,427,000,000
Goodwill	4,729,000,000		4,704,000,000
Intangible assets	2,631,000,000		2,633,000,000
Investments in consolidated subsidiaries	0		0
Other assets	2,381,000,000		2,549,000,000
Intercompany	28,051,000,000		26,976,000,000
Assets of discontinued operations	3,577,000,000		4,288,000,000
Total Assets	50,566,000,000		50,320,000,000
Liabilities and Stockholders' Equity [Abstract]
Accounts payable	156,000,000		144,000,000
Participants' share and royalties payable	1,022,000,000		1,024,000,000
Program rights	470,000,000		282,000,000
Commercial paper	0		0
Current portion of long-term debt (Note 6)	17,000,000		17,000,000
Accrued expenses and other current liabilities	1,014,000,000		948,000,000
Current liabilities of discontinued operations	151,000,000		155,000,000
Total current liabilities	2,830,000,000		2,570,000,000
Long-term debt (Note 6)	101,000,000		104,000,000
Other liabilities	2,180,000,000		2,173,000,000
Liabilities of discontinued operations	2,454,000,000		2,451,000,000
Intercompany	0		0
Stockholders' Equity [Abstract]
Preferred stock	126,000,000		126,000,000
Common stock	590,000,000		590,000,000
Additional paid-in capital	60,894,000,000		60,894,000,000
Retained earnings (accumulated deficit)	(13,865,000,000)		(13,838,000,000)
Accumulated other comprehensive income (loss)	56,000,000		50,000,000
Stockholders' equity including treasury stock	47,801,000,000		47,822,000,000
Less treasury stock, at cost	4,800,000,000		4,800,000,000
Total Stockholders' Equity	43,001,000,000		43,022,000,000
Total Liabilities and Stockholders' Equity	50,566,000,000		$ 50,320,000,000
Condensed Consolidating Statement Of Cash Flows [Abstract]
Net cash flow provided by (used for) operating activities	1,093,000,000	1,288,000,000
Investing Activities
Acquisitions	(21,000,000)	(50,000,000)
Capital expenditures	(23,000,000)	(25,000,000)
Investments in and advances to investee companies	(49,000,000)	(32,000,000)
Proceeds from dispositions	1,000,000	23,000,000
Other investing activities	0	0
Net cash flow provided by (used for) investing activities from continuing operations	(92,000,000)	(84,000,000)
Net cash flow provided by (used for) investing activities from discontinued operations	(6,000,000)	4,000,000
Net cash flow provided by (used for) investing activities	(98,000,000)	(80,000,000)
Financing Activities
Proceeds from (repayments of) short-term debt borrowings, net	0
Repayment of senior debentures		0
Repayment of debt borrowings of CBS Radio	(3,000,000)
Payment of capital lease obligations	(4,000,000)	(4,000,000)
Payment of contingent consideration	(7,000,000)
Dividends	0	0
Purchase of Company common stock	0	0
Payment of payroll taxes in lieu of issuing shares for stock-based compensation	0	0
Proceeds from exercise of stock options	0	0
Excess tax benefit from stock-based compensation		0
Increase (decrease) in intercompany payables	(1,156,000,000)	(1,019,000,000)
Net cash flow provided by (used for) financing activities	(1,170,000,000)	(1,023,000,000)
Net increase (decrease) in cash and cash equivalents	(175,000,000)	185,000,000
Cash and cash equivalents, including discontinued operations, at beginning of period	301,000,000	55,000,000
Cash and cash equivalents, including discontinued operations, at end of period	$ 126,000,000	$ 240,000,000