CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue	$ 1,472	$ 1,275	$ 4,436	$ 4,178
Expenses
Operating	412	393	1,266	1,203
Selling, general, and administrative	403	385	1,204	1,124
Depreciation and amortization	95	83	276	242
Restructuring	27	1	51	32
Total expenses	937	862	2,797	2,601
Operating income	535	413	1,639	1,577
Non-operating (expense) income, net
Interest expense, net	(66)	(58)	(185)	(166)
Other non-operating income, net	18	26	31	22
Total non-operating (expense) income, net	(48)	(32)	(154)	(144)
Income before provision for income taxes	487	381	1,485	1,433
Provision for income taxes	97	78	217	305
Net Income	390	303	1,268	1,128
Less: Net income attributable to noncontrolling interests	1	0	1	0
Net income (loss) attributable to parent	$ 389	$ 303	$ 1,267	$ 1,128
Earnings per share attributable to Moody's common shareholders
Basic (in usd per share)	$ 2.12	$ 1.65	$ 6.91	$ 6.13
Diluted (in usd per share)	$ 2.11	$ 1.65	$ 6.88	$ 6.10
Weighted average number of shares outstanding
Basic (in shares)	183.3	183.2	183.4	184.1
Diluted (in shares)	184.0	183.9	184.1	184.9