Debt Obligations (1.75% Senior Unsecured Notes) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Debt Instrument [Line Items]
Increase in carrying amount	$ (74)
Senior Notes \| 1.75% senior unsecured notes due May 19, 2023
Debt Instrument [Line Items]
Stated rate	1.75%
Increase in carrying amount	$ 20
Maximum \| Senior Notes \| 1.75% senior unsecured notes due May 19, 2023
Debt Instrument [Line Items]
Maximum interest rate on debt instrument	3.75%

Payments (Accretions) And Other of Long-term Debt

No definition available.

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Namespace Prefix:	ndaq_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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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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- Details

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- Details

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Balance Type:
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- Details

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