Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenue	$ 1,567	$ 1,453
Expenses:
Operating-related expenses	439	411
Selling and general expenses	372	360
Depreciation	21	19
Amortization of intangibles	24	24
Total expenses	856	814
Operating profit	711	639
Other (income) expense, net	(4)	(9)
Interest expense, net	34	37
Income before taxes on income	681	611
Provision for taxes on income	147	181
Net income	534	430
Less: net income attributable to noncontrolling interests	(43)	(31)
Net income attributable to S&P Global Inc.	$ 491	$ 399
Net income:
Basic (USD per share)	$ 1.94	$ 1.54
Diluted (USD per share)	$ 1.93	$ 1.53
Weighted-average number of common shares outstanding:
Basic (shares)	252.4	258.2
Diluted (shares)	254.4	260.8
Actual shares outstanding at period end (shares)	249.4	257.8
Dividend declared per common share (USD per share)	$ 0.5	$ 0.41