Percentage of assets as to total pension plan assets.

No definition available.

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- Definition

Defined Contribution Plan, Eligible Pay Threshold

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Employee Benefit Plans - Narrative (Details) - USD ($)	12 Months Ended
Employee Benefit Plans - Narrative (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension and Other Postretirement Plans
Expected contributions by employer in 2021	$ 40,000,000
Morgan Stanley 401(k) Plan
Pension and Other Postretirement Plans
Maximum proportion of employer matching contributions (as a percent)	4.00%	4.00%	4.00%
Morgan Stanley 401(k) Plan \| Participants of a Certain Compensation Level
Pension and Other Postretirement Plans
Maximum proportion of employer matching contributions (as a percent)	5.00%
Morgan Stanley 401(k) Plan \| Eligible U.S. Employees with Eligible Pay Less than or Equal to $100,000
Pension and Other Postretirement Plans
Eligible pay threshold	$ 100,000
Proportion of employer matching contribution of eligible pay (as a percent)	2.00%
U.S. Qualified Plan
Pension and Other Postretirement Plans
Proportion of assets as to total pension plan assets (as a percent)	86.00%