Condensed Consolidating Financial Statements (Statement of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	$ 923	$ 281	$ 1,659	$ 992
Adjustments to reconcile net income to cash provided by (used for) operating activities from continuing operations:
Depreciation			63	64
Amortization of intangibles			71	40
Provision for losses on accounts receivable			10	3
Deferred income taxes			(8)	166
Stock-based compensation			54	55
Gain on dispositions	(722)	0	(722)	(11)
Other			56	150
Changes in operating assets and liabilities, net of effect of acquisitions and dispositions:
Accounts receivable			(26)	(44)
Prepaid and other current assets			(2)	(6)
Accounts payable and accrued expenses			(127)	(186)
Unearned revenue			(6)	18
Accrued legal and regulatory settlements			(134)	(1,624)
Other current liabilities			(12)	(53)
Net change in prepaid/accrued income taxes			352	140
Net change in other assets and liabilities			(57)	(60)
Cash provided by (used for) operating activities from continuing operations			1,171	(356)
Investing Activities:
Capital expenditures			(67)	(74)
Acquisitions, net of cash acquired			(145)	(2,393)
Proceeds from dispositions			1,071	14
Changes in short-term investments			(1)	(3)
Cash provided by (used for) investing activities from continuing operations			858	(2,456)
Financing Activities:
Payments on short-term debt, net			(143)	0
Proceeds from issuance of senior notes, net			493	2,674
Dividends paid to shareholders			(286)	(274)
Dividends and other payments paid to noncontrolling interests			(59)	(67)
Contingent consideration payment			(15)	(5)
Purchase of CRISIL shares			0	(16)
Repurchase of treasury shares			(1,123)	(501)
Exercise of stock options			84	77
Excess tax benefits from share-based payments			31	39
Intercompany financing activities			0	0
Cash (used for) provided by financing activities from continuing operations			(1,018)	1,927
Effect of exchange rate changes on cash from continuing operations			(93)	(42)
Cash provided by (used for) continuing operations			918	(927)
Discontinued Operations:
Cash used for operating activities			0	(129)
Cash used for discontinued operations			0	(129)
Net change in cash and cash equivalents			918	(1,056)
Cash and cash equivalents at beginning of period			1,481	2,497
Cash and cash equivalents at end of period	2,399	1,441	2,399	1,441
Eliminations
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	(581)	(1,386)	(2,637)	(1,385)
Adjustments to reconcile net income to cash provided by (used for) operating activities from continuing operations:
Depreciation			0	0
Amortization of intangibles			0	0
Provision for losses on accounts receivable			0	0
Deferred income taxes			0	0
Stock-based compensation			0	0
Gain on dispositions	0		0	0
Other			0	0
Changes in operating assets and liabilities, net of effect of acquisitions and dispositions:
Accounts receivable			0	0
Prepaid and other current assets			0	0
Accounts payable and accrued expenses			0	0
Unearned revenue			0	0
Accrued legal and regulatory settlements			0	0
Other current liabilities			0	0
Net change in prepaid/accrued income taxes			0	0
Net change in other assets and liabilities			0	0
Cash provided by (used for) operating activities from continuing operations			(2,637)	(1,385)
Investing Activities:
Capital expenditures			0	0
Acquisitions, net of cash acquired			0	0
Proceeds from dispositions			0	0
Changes in short-term investments			0	0
Cash provided by (used for) investing activities from continuing operations			0	0
Financing Activities:
Payments on short-term debt, net			0
Proceeds from issuance of senior notes, net			0	0
Dividends paid to shareholders			0	0
Dividends and other payments paid to noncontrolling interests			0	0
Contingent consideration payment			0	0
Purchase of CRISIL shares				0
Repurchase of treasury shares			0	0
Exercise of stock options			0	0
Excess tax benefits from share-based payments			0	0
Intercompany financing activities			2,637	1,385
Cash (used for) provided by financing activities from continuing operations			2,637	1,385
Effect of exchange rate changes on cash from continuing operations			0	0
Cash provided by (used for) continuing operations				0
Discontinued Operations:
Cash used for operating activities				0
Cash used for discontinued operations				0
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	0	0	0
S&P Global Inc.
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	1,016	1,101	2,341	1,094
Adjustments to reconcile net income to cash provided by (used for) operating activities from continuing operations:
Depreciation			28	29
Amortization of intangibles			0	0
Provision for losses on accounts receivable			2	0
Deferred income taxes			(80)	(139)
Stock-based compensation			17	16
Gain on dispositions	(705)		(705)	0
Other			14	107
Changes in operating assets and liabilities, net of effect of acquisitions and dispositions:
Accounts receivable			5	10
Prepaid and other current assets			(14)	(35)
Accounts payable and accrued expenses			(70)	(100)
Unearned revenue			20	10
Accrued legal and regulatory settlements			0	0
Other current liabilities			(17)	(19)
Net change in prepaid/accrued income taxes			297	166
Net change in other assets and liabilities			(35)	91
Cash provided by (used for) operating activities from continuing operations			1,803	1,230
Investing Activities:
Capital expenditures			(34)	(38)
Acquisitions, net of cash acquired			(140)	(2,241)
Proceeds from dispositions			1,047	0
Changes in short-term investments			0	0
Cash provided by (used for) investing activities from continuing operations			873	(2,279)
Financing Activities:
Payments on short-term debt, net			(143)
Proceeds from issuance of senior notes, net			493	2,674
Dividends paid to shareholders			(286)	(274)
Dividends and other payments paid to noncontrolling interests			0	0
Contingent consideration payment			(5)	(5)
Purchase of CRISIL shares				0
Repurchase of treasury shares			(1,123)	(501)
Exercise of stock options			83	76
Excess tax benefits from share-based payments			31	39
Intercompany financing activities			(1,155)	(2,192)
Cash (used for) provided by financing activities from continuing operations			(2,105)	(183)
Effect of exchange rate changes on cash from continuing operations			0	(9)
Cash provided by (used for) continuing operations				(1,241)
Discontinued Operations:
Cash used for operating activities				0
Cash used for discontinued operations				0
Net change in cash and cash equivalents			571	(1,241)
Cash and cash equivalents at beginning of period			167	1,402
Cash and cash equivalents at end of period	738	161	738	161
Standard & Poor's Financial Services LLC
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	223	409	663	762
Adjustments to reconcile net income to cash provided by (used for) operating activities from continuing operations:
Depreciation			7	14
Amortization of intangibles			0	0
Provision for losses on accounts receivable			0	(4)
Deferred income taxes			0	161
Stock-based compensation			12	16
Gain on dispositions	0		0	0
Other			3	22
Changes in operating assets and liabilities, net of effect of acquisitions and dispositions:
Accounts receivable			159	16
Prepaid and other current assets			13	22
Accounts payable and accrued expenses			(147)	(76)
Unearned revenue			(385)	(20)
Accrued legal and regulatory settlements			(108)	(1,624)
Other current liabilities			(25)	(12)
Net change in prepaid/accrued income taxes			0	0
Net change in other assets and liabilities			29	4
Cash provided by (used for) operating activities from continuing operations			221	(719)
Investing Activities:
Capital expenditures			(11)	(7)
Acquisitions, net of cash acquired			0	0
Proceeds from dispositions			0	0
Changes in short-term investments			0	0
Cash provided by (used for) investing activities from continuing operations			(11)	(7)
Financing Activities:
Payments on short-term debt, net			0
Proceeds from issuance of senior notes, net			0	0
Dividends paid to shareholders			0	0
Dividends and other payments paid to noncontrolling interests			0	0
Contingent consideration payment			0	0
Purchase of CRISIL shares				0
Repurchase of treasury shares			0	0
Exercise of stock options			0	0
Excess tax benefits from share-based payments			0	0
Intercompany financing activities			(210)	727
Cash (used for) provided by financing activities from continuing operations			(210)	727
Effect of exchange rate changes on cash from continuing operations			0	0
Cash provided by (used for) continuing operations				1
Discontinued Operations:
Cash used for operating activities				0
Cash used for discontinued operations				0
Net change in cash and cash equivalents			0	1
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	1	0	1
Non-Guarantor Subsidiaries
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	265	157	1,292	521
Adjustments to reconcile net income to cash provided by (used for) operating activities from continuing operations:
Depreciation			28	21
Amortization of intangibles			71	40
Provision for losses on accounts receivable			8	7
Deferred income taxes			72	144
Stock-based compensation			25	23
Gain on dispositions	(17)		(17)	(11)
Other			39	21
Changes in operating assets and liabilities, net of effect of acquisitions and dispositions:
Accounts receivable			(190)	(70)
Prepaid and other current assets			(1)	7
Accounts payable and accrued expenses			90	(10)
Unearned revenue			359	28
Accrued legal and regulatory settlements			(26)	0
Other current liabilities			30	(22)
Net change in prepaid/accrued income taxes			55	(26)
Net change in other assets and liabilities			(51)	(155)
Cash provided by (used for) operating activities from continuing operations			1,784	518
Investing Activities:
Capital expenditures			(22)	(29)
Acquisitions, net of cash acquired			(5)	(152)
Proceeds from dispositions			24	14
Changes in short-term investments			(1)	(3)
Cash provided by (used for) investing activities from continuing operations			(4)	(170)
Financing Activities:
Payments on short-term debt, net			0
Proceeds from issuance of senior notes, net			0	0
Dividends paid to shareholders			0	0
Dividends and other payments paid to noncontrolling interests			(59)	(67)
Contingent consideration payment			(10)	0
Purchase of CRISIL shares				(16)
Repurchase of treasury shares			0	0
Exercise of stock options			1	1
Excess tax benefits from share-based payments			0	0
Intercompany financing activities			(1,272)	80
Cash (used for) provided by financing activities from continuing operations			(1,340)	(2)
Effect of exchange rate changes on cash from continuing operations			(93)	(33)
Cash provided by (used for) continuing operations				313
Discontinued Operations:
Cash used for operating activities				(129)
Cash used for discontinued operations				(129)
Net change in cash and cash equivalents			347	184
Cash and cash equivalents at beginning of period			1,314	1,095
Cash and cash equivalents at end of period	$ 1,661	$ 1,279	$ 1,661	$ 1,279