Forward starting interest rate swap agreement, fixed rate

No definition available.

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Namespace Prefix:	cme_
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Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Balance Type:	credit
Period Type:	instant

- 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
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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.

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Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Period Type:	duration

- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ 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
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- Details

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Debt (Schedule Of Short-Term And Long-Term Debt) (Details) € in Millions, $ in Millions	1 Months Ended			6 Months Ended
	Mar. 31, 2015	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2020 USD ($)	Jun. 30, 2020 EUR (€)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Long-term debt				$ 3,440.9		$ 3,743.2
Forward starting interest rate swap agreement fixed rate	3.11%	4.73%	3.32%
$750.0 million Fixed Rate Notes Due September 2022, stated rate of 3.00% [Member]
Debt Instrument [Line Items]
Long-term debt				748.1		747.7
Debt Instrument, Face Amount				$ 750.0
Debt Instrument, Maturity Date				Sep. 15, 2022
Debt Instrument, Interest Rate, Stated Percentage				3.00%	3.00%
€15.0 million fixed rate notes due May 2023 [Member]
Debt Instrument [Line Items]
Long-term debt				$ 16.5		16.4
Debt Instrument, Face Amount \| €					€ 15.0
Debt Instrument, Maturity Date				May 01, 2023
Debt Instrument, Interest Rate, Stated Percentage				4.30%	4.30%
$750.0 Million Fixed Rate Notes Due March 2025, stated rate of 3.00% [Member]
Debt Instrument [Line Items]
Long-term debt				$ 746.7		746.3
Debt Instrument, Face Amount				$ 750.0
Debt Instrument, Maturity Date				Mar. 15, 2025
Debt Instrument, Interest Rate, Stated Percentage				3.00%	3.00%
$500.0 Million Fixed Rate Notes Due June 2028, stated rate of 3.75% [Member] [Domain]
Debt Instrument [Line Items]
Long-term debt				$ 496.6		496.4
Debt Instrument, Face Amount				$ 500.0
Debt Instrument, Maturity Date				Jun. 15, 2028
Debt Instrument, Interest Rate, Stated Percentage				3.75%	3.75%
$750.0 million Fixed Rate Notes Due September 2043, stated rate of 5.30% [Member]
Debt Instrument [Line Items]
Long-term debt				$ 742.9		742.8
Debt Instrument, Face Amount				$ 750.0
Debt Instrument, Maturity Date				Sep. 15, 2043
Debt Instrument, Interest Rate, Stated Percentage				5.30%	5.30%
$700.0 Million Fixed Rate Notes Due June 2048, stated rate of 4.15% [Member] [Domain] [Domain]
Debt Instrument [Line Items]
Long-term debt				$ 690.1		689.8
Debt Instrument, Face Amount				$ 700.0
Debt Instrument, Maturity Date				Jun. 15, 2048
Debt Instrument, Interest Rate, Stated Percentage				4.15%	4.15%
Commercial Paper [Member]
Debt Instrument [Line Items]
Long-term debt				$ 0.0		$ 303.8