Percentage of assets as to total pension plan assets.

No definition available.

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- Definition

Description of employer's matching contribution to defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

+ Details

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

+ Details

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Balance Type:	debit
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- 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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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:	num:percentItemType
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- Details

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Employee Benefit Plans (Narratives) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Information about Plan Assets
Accumulated benefit obligation	$ 3,988	$ 3,309
Estimated contributions by employer in next year	50
U.S. Qualified Plan
Information about Plan Assets
Percentage as to total pension plan assets	88.00%
Morgan Stanley 401(k) Plan
Defined Contribution Pension and Other Postretirement Plans
Description of employer matching contribution	Eligible U.S. employees receive discretionary 401(k) matching cash contributions as determined annually by the Company. For 2014 and 2013, the Company made a $1 for $1 Company match up to 4% of eligible pay, up to the Internal Revenue Service (“IRS”) limit.
Maximum percent of employer matching contributions	4.00%
Expense related to defined contribution plans	256	242	246
Morgan Stanley 401(k) Plan \| Eligible U.S. Employees with Eligible Pay Less than or Equal to $100,000
Defined Contribution Pension and Other Postretirement Plans
Percent of employer matching contribution	2.00%
Pension
Information about Plan Assets
Estimated prior-service credit that will be amortized from accumulated other comprehensive loss into net periodic benefit expense over 2014	1
Estimated net loss that will be amortized from accumulated other comprehensive loss into net periodic benefit expense over 2014	26
Defined Contribution Pension and Other Postretirement Plans
Expense related to defined contribution plans	117	111	126
Postretirement
Information about Plan Assets
Estimated prior-service credit that will be amortized from accumulated other comprehensive loss into net periodic benefit expense over 2014	$ 19