Segment, Geographic and Revenue Information - Revenue Recognized from Prior Services (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting [Abstract]
Non-interest revenues	$ 2,303	$ 1,870	$ 1,778

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