Segment, Geographic and Revenue Information - Revenue Recognized from Prior Services (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting [Abstract]
Non-interest revenues	$ 566	$ 468	$ 1,416	$ 1,350

Revenue recognized in the reporting period from performance obligations satisfied (or partially satisfied) in previous periods.

No definition available.

Name:	ms_RevenueFromContractWithCustomerPerformanceObligationsFullyOrPartiallySatisfiedInPriorPeriods
Namespace Prefix:	ms_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration