CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net Income	$ 377	$ 327	$ 878	$ 825
Other Comprehensive Income (Loss):
Foreign currency translation adjustments - Pre Tax	51	(340)	160	(448)
Foreign currency translation adjustments - Tax	0	3	(2)	4
Foreign currency translation adjustments - Net of Tax	51	(337)	158	(444)
Foreign currency translation adjustments - reclassification of losses included in net income - Pre tax	0	20	0	20
Foreign currency translation adjustments - reclassification of losses included in net income, Tax	0	0	0	0
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Reclassification, Net of Tax	0	20	0	20
Net gains on net investment hedges - Pre Tax	(37)	241	(113)	305
Net gains on net investment hedges - Tax	9	(60)	28	(77)
Net gains on net investment hedges - Net of Tax	(28)	181	(85)	228
Cash Flow Hedges:
Reclassification of losses included in net income - Pre Tax	0	0	1	1
Reclassification of losses included in net income - Tax	(1)	0	(1)	0
Reclassification of losses included in net income - Net of Tax	(1)	0	0	1
Pension and Other Retirement Benefits:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	(2)	1	(2)	1
Amortization of actuarial losses and prior service costs included in net income, tax expense (benefit)	1	0	1	0
Amortization of actuarial losses and prior service costs included in net income - Net of tax	(1)	1	(1)	1
Net actuarial (losses) and prior service costs - Pre Tax	0	6	0	3
Net actuarial (losses) and prior service costs - Tax	0	(2)	0	(1)
Net actuarial (losses) and prior service costs - Net of Tax	0	4	0	2
Total other comprehensive income (loss) - Pre Tax	12	(72)	46	(118)
Total other comprehensive income (loss) - Tax	9	(59)	26	(74)
Total other comprehensive income (loss) - Net of Tax	21	(131)	72	(192)
Comprehensive income	398	196	950	633
Less: comprehensive income (loss) attributable to noncontrolling interests	2	(3)	(1)	(3)
Comprehensive Income Attributable to Moody's	$ 396	$ 199	$ 951	$ 636