CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Revenue	$ 1,817	$ 1,494	$ 3,603	$ 2,964
Expenses
Operating	469	426	936	854
Selling, general, and administrative	446	415	859	801
Depreciation and amortization	110	93	210	181
Restructuring	2	10	7	24
Charges related to asset abandonment	15	0	15	0
Total expenses	1,042	944	2,027	1,860
Operating income	775	550	1,576	1,104
Non-operating (expense) income, net
Interest expense, net	(63)	(71)	(125)	(119)
Other non-operating income, net	7	13	20	13
Total non-operating (expense) income, net	(56)	(58)	(105)	(106)
Income before provision for income taxes	719	492	1,471	998
Provision for income taxes	166	115	341	120
Net Income	553	377	1,130	878
Less: Net income attributable to noncontrolling interests	1	0	1	0
Net income attributable to Moody's	$ 552	$ 377	$ 1,129	$ 878
Earnings per share attributable to Moody's common shareholders
Basic (in usd per share)	$ 3.03	$ 2.05	$ 6.19	$ 4.79
Diluted (in usd per share)	$ 3.02	$ 2.05	$ 6.16	$ 4.77
Weighted average number of shares outstanding
Basic (in shares)	182.3	183.5	182.5	183.4
Diluted (in shares)	183.0	184.1	183.2	184.1