Line Of Credit Facility, Optional Increase In Maximum Borrowing Capacity

No definition available.

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

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

- Details

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- Details

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- Details

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Debt Obligations (2017 Credit Facility) (Details) - USD ($)	1 Months Ended			9 Months Ended
	Apr. 30, 2020	Mar. 31, 2020	Apr. 30, 2017	Sep. 30, 2020	Jun. 30, 2020
Debt Instrument [Line Items]
Net proceeds from senior note				$ 1,928,000,000
$1 billion senior unsecured revolving credit facility due April 25, 2022
Debt Instrument [Line Items]
Unamortized debt issuance expense				$ (2,000,000)
3.25% senior unsecured notes due April 28, 2050
Debt Instrument [Line Items]
Stated rate				3.25%
Revolving Credit Facility \| $1 billion senior unsecured revolving credit facility due April 25, 2022
Debt Instrument [Line Items]
Credit facility, borrowing capacity			$ 1,000,000,000
Credit facility term			5 years
Remaining amount available				$ 1,000,000,000
Option to increase available aggregate amount				$ 500,000,000
Revolving Credit Facility \| $1 billion senior unsecured revolving credit facility due April 25, 2022 \| Minimum
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage				0.125%
Revolving Credit Facility \| $1 billion senior unsecured revolving credit facility due April 25, 2022 \| Maximum
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage				0.40%
Senior Notes \| 3.25% senior unsecured notes due April 28, 2050
Debt Instrument [Line Items]
Net proceeds from senior note	$ 485,000,000			$ 485,000,000
Stated rate					3.25%
Senior Notes \| 3.25% senior unsecured notes due April 28, 2050 \| Maximum
Debt Instrument [Line Items]
Stated rate	5.25%
$1 billion senior unsecured revolving credit facility due April 25, 2022
Debt Instrument [Line Items]
Credit facility, borrowing capacity				1,000,000,000
Net proceeds from senior note		$ 799,000,000		$ 799,000,000