Loans, Lending Commitments and Related Allowance for Credit Losses - Narrative (Details) - loan	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
90+ days past due
Financing Receivable, Modified [Line Items]
Number of investments	0	0

Financing Receivable, Excluding Accrued Interest, Number of Defaulted and Modified Investments

No definition available.

Name:	ms_FinancingReceivableExcludingAccruedInterestNumberOfDefaultedAndModifiedInvestments
Namespace Prefix:	ms_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration