Debt Instrument, Leverage Ratio Requirement

No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3044-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6676-107765

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: 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))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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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

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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- Details

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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=dgx_SeniorunsecuredrevolvingcreditfacilityMember
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- Details

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DEBT (Credit Facilities) (Details) - USD ($)	6 Months Ended
DEBT (Credit Facilities) (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Cash and cash equivalents	$ 988,000,000							$ 1,192,000,000
Proceeds from borrowings	749,000,000	$ 1,484,000,000
Credit Facilities
Debt Instrument [Line Items]
Remaining borrowing capacity	1,300,000,000
Amount outstanding	0
Secured Receivables Credit Facility
Debt Instrument [Line Items]
Remaining borrowing capacity	529,000,000
Proceeds from borrowings	100,000,000
Extinguishment of debt	100,000,000
Secured Receivables Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Credit facility capacity	100,000,000
Secured Receivables Credit Facility \| Loan commitment maturing October 2020
Debt Instrument [Line Items]
Credit facility capacity	250,000,000
Secured Receivables Credit Facility \| Loan commitment maturing October 2021
Debt Instrument [Line Items]
Credit facility capacity	250,000,000
Senior Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Remaining borrowing capacity	750,000,000
Proceeds from borrowings	100,000,000
Extinguishment of debt	$ 100,000,000
Senior Unsecured Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Leverage ratio	500.00%
Senior Unsecured Revolving Credit Facility \| Maximum \| Scenario, Forecast
Debt Instrument [Line Items]
Leverage ratio			350.00%	450.00%	625.00%	650.00%	550.00%