For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

+ Details

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

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=dgx_NewYorkPresbyterianMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=dgx_HaystackOncologyIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions	Apr. 17, 2023	Apr. 28, 2023	Mar. 31, 2023	Mar. 31, 2022
Subsequent Event [Line Items]
Cash paid for business acquisitions			$ 31	$ 109
Subsequent Event \| New York-Presbyterian
Subsequent Event [Line Items]
Cash paid for business acquisitions	$ 275
Subsequent Event \| Haystack Oncology, Inc. \| Plan
Subsequent Event [Line Items]
Cash paid for business acquisitions		$ 300
Maximum contingent consideration payment		$ 150