Condensed Consolidating Financial Statements - Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,881		$ 1,917
Restricted cash	39		41
Accounts receivable, net of allowance for doubtful accounts	1,543		1,449
Intercompany receivable	0		0
Prepaid and other current assets	231		197
Total current assets	3,694		3,604
Property and equipment, net of accumulated depreciation	280		270
Right of use assets	669		0
Goodwill	3,519		3,535
Other intangible assets, net	1,453		1,524
Investments in subsidiaries	0		0
Intercompany loans receivable	0		0
Other non-current assets	570		525
Total assets	10,185		9,458
Current liabilities:
Accounts payable	214		211
Intercompany payable	0		0
Accrued compensation and contributions to retirement plans	269		354
Income taxes currently payable	88		72
Unearned revenue	1,709		1,641
Other current liabilities	419		351
Total current liabilities	2,699		2,629
Long-term debt	3,664		3,662
Lease liabilities — non-current	621		0
Intercompany loans payable	0		0
Pension and other postretirement benefits	230		229
Other non-current liabilities	511		634
Total liabilities	7,725		7,154
Redeemable noncontrolling interest	1,890		1,620
Equity:
Common stock	294		294
Additional paid-in capital	790		833
Retained income	11,710		11,284
Accumulated other comprehensive loss	(651)		(742)
Less: common stock in treasury	(11,631)		(11,041)
Total equity — controlling interests	512		628
Total equity - noncontrolling interests	58		56
Total equity	570	$ 388	684	$ 633	$ 65	$ 768
Total liabilities and equity	10,185		9,458
Eliminations
Current assets:
Cash and cash equivalents	0		0
Restricted cash	0		0
Accounts receivable, net of allowance for doubtful accounts	0		0
Intercompany receivable	(6,196)		(5,561)
Prepaid and other current assets	0		0
Total current assets	(6,196)		(5,561)
Property and equipment, net of accumulated depreciation	0		0
Right of use assets	0		0
Goodwill	7		9
Other intangible assets, net	0		0
Investments in subsidiaries	(18,645)		(16,635)
Intercompany loans receivable	(1,274)		(1,773)
Other non-current assets	(1)		0
Total assets	(26,109)		(23,960)
Current liabilities:
Accounts payable	0		0
Intercompany payable	(6,196)		(5,561)
Accrued compensation and contributions to retirement plans	0		0
Income taxes currently payable	0		0
Unearned revenue	0		0
Other current liabilities	0		0
Total current liabilities	(6,196)		(5,561)
Long-term debt	0		0
Lease liabilities — non-current	0		0
Intercompany loans payable	(1,274)		(1,773)
Pension and other postretirement benefits	0		0
Other non-current liabilities	0		0
Total liabilities	(7,470)		(7,334)
Redeemable noncontrolling interest	1,890		1,620
Equity:
Common stock	(2,371)		(2,279)
Additional paid-in capital	(9,537)		(9,641)
Retained income	(8,721)		(6,439)
Accumulated other comprehensive loss	43		46
Less: common stock in treasury	0		12
Total equity — controlling interests	(20,586)		(18,301)
Total equity - noncontrolling interests	57		55
Total equity	(20,529)		(18,246)
Total liabilities and equity	(26,109)		(23,960)
S&P Global Inc. | Reportable Legal Entities
Current assets:
Cash and cash equivalents	556		694
Restricted cash	0		0
Accounts receivable, net of allowance for doubtful accounts	269		163
Intercompany receivable	585		550
Prepaid and other current assets	45		58
Total current assets	1,455		1,465
Property and equipment, net of accumulated depreciation	205		192
Right of use assets	404		0
Goodwill	261		261
Other intangible assets, net	0		0
Investments in subsidiaries	10,631		8,599
Intercompany loans receivable	137		130
Other non-current assets	208		194
Total assets	13,301		10,841
Current liabilities:
Accounts payable	100		89
Intercompany payable	5,107		4,453
Accrued compensation and contributions to retirement plans	108		125
Income taxes currently payable	18		1
Unearned revenue	268		240
Other current liabilities	187		180
Total current liabilities	5,788		5,088
Long-term debt	3,664		3,662
Lease liabilities — non-current	386		0
Intercompany loans payable	120		114
Pension and other postretirement benefits	162		162
Other non-current liabilities	131		166
Total liabilities	10,251		9,192
Redeemable noncontrolling interest	0		0
Equity:
Common stock	294		294
Additional paid-in capital	26		72
Retained income	14,569		12,622
Accumulated other comprehensive loss	(209)		(299)
Less: common stock in treasury	(11,630)		(11,040)
Total equity — controlling interests	3,050		1,649
Total equity - noncontrolling interests	0		0
Total equity	3,050		1,649
Total liabilities and equity	13,301		10,841
Standard & Poor's Financial Services LLC | Reportable Legal Entities
Current assets:
Cash and cash equivalents	0		0
Restricted cash	0		0
Accounts receivable, net of allowance for doubtful accounts	195		109
Intercompany receivable	2,330		2,138
Prepaid and other current assets	0		3
Total current assets	2,525		2,250
Property and equipment, net of accumulated depreciation	0		0
Right of use assets	2		0
Goodwill	0		0
Other intangible assets, net	0		0
Investments in subsidiaries	6		6
Intercompany loans receivable	0		0
Other non-current assets	43		45
Total assets	2,576		2,301
Current liabilities:
Accounts payable	7		15
Intercompany payable	55		32
Accrued compensation and contributions to retirement plans	27		33
Income taxes currently payable	0		0
Unearned revenue	259		235
Other current liabilities	20		16
Total current liabilities	368		331
Long-term debt	0		0
Lease liabilities — non-current	1		0
Intercompany loans payable	0		0
Pension and other postretirement benefits	0		0
Other non-current liabilities	76		75
Total liabilities	445		406
Redeemable noncontrolling interest	0		0
Equity:
Common stock	0		0
Additional paid-in capital	622		618
Retained income	1,509		1,277
Accumulated other comprehensive loss	0		0
Less: common stock in treasury	0		0
Total equity — controlling interests	2,131		1,895
Total equity - noncontrolling interests	0		0
Total equity	2,131		1,895
Total liabilities and equity	2,576		2,301
Non-Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and cash equivalents	1,325		1,223
Restricted cash	39		41
Accounts receivable, net of allowance for doubtful accounts	1,079		1,177
Intercompany receivable	3,281		2,873
Prepaid and other current assets	186		136
Total current assets	5,910		5,450
Property and equipment, net of accumulated depreciation	75		78
Right of use assets	263		0
Goodwill	3,251		3,265
Other intangible assets, net	1,453		1,524
Investments in subsidiaries	8,008		8,030
Intercompany loans receivable	1,137		1,643
Other non-current assets	320		286
Total assets	20,417		20,276
Current liabilities:
Accounts payable	107		107
Intercompany payable	1,034		1,076
Accrued compensation and contributions to retirement plans	134		196
Income taxes currently payable	70		71
Unearned revenue	1,182		1,166
Other current liabilities	212		155
Total current liabilities	2,739		2,771
Long-term debt	0		0
Lease liabilities — non-current	234		0
Intercompany loans payable	1,154		1,659
Pension and other postretirement benefits	68		67
Other non-current liabilities	304		393
Total liabilities	4,499		4,890
Redeemable noncontrolling interest	0		0
Equity:
Common stock	2,371		2,279
Additional paid-in capital	9,679		9,784
Retained income	4,353		3,824
Accumulated other comprehensive loss	(485)		(489)
Less: common stock in treasury	(1)		(13)
Total equity — controlling interests	15,917		15,385
Total equity - noncontrolling interests	1		1
Total equity	15,918		15,386
Total liabilities and equity	$ 20,417		$ 20,276